Table of Contents
Overview

3

Campus map

4

Wifi

4

Excursion

5

Banquet5

Scientific program

6

List of poster

9

Abstract
YCA lecture

13

Session 1

15

Session 2

34

Session 3

76

Session4

139

Overview
9:30
10:00
10:30

7 Nov (Tue)opening(Session 1)
O1_001IO1_002
O1_003Coffee break

11:00
11:30

O1_004I
O1_005I
O1_00612:00

O1_0078 Nov (Wed)

9 Nov (Thu)(Session 4)
O4_020K(Session 3)
O3_033K

10 Nov (Fri)(Session 3)
O3_040IO3_041

O4_021IO3_034I

O3_042

O4_047

O3_035

O3_043Coffee BreakO3_036(Session 2)
O2_018K

O3_037(Session 3)
O3_022IO3_023O3_038Break(Session 4)
O4_044K
O4_045

Lunch

O4_046

O1_00812:30
13:00

Young Career Award
Lunch

Lunch
YCA lecture YCA_039

13:30
14:00
14:30
15:00

O1_009I(Session 2)
O2_010K
O2_011O2_012

15:30
16:00
16:30
17:00

Poster & Coffee breakO2_013IO2_014
O2_01517:30

02_016
O2_01718:00
7 Nov (Tue)

Lunch(Session 2)
O2_019IO2_048(Session 4)
O4_049IO3_024K
O3_025

O4_050IO3_02603_027

O4_051

O3_028
Excursion

Closing, Award,
and Remarks

Banquet9 Nov (Thu)

10 Nov (Fri)Poster & Coffee breakO3_029K
O3_030O3_031(Session 1)
O1_032I
8 Nov (Wed)Campus map

Conference
venue

Wifi

Wireless LAN (SSIDeduroam) is available in the venue of APSPM 2017.
Those who belongs to the institute of eduroam, please prepare your eduroam
account at each institute in advance.
For the information of institute, please checkhttps://www.eduroam.org/
or
http://www.eduroam.jp/participants/siteinfo.html (Japan).
For non-members, we will prepare eduroam accounts for visitors.

Excursion
Excursion to Kwasan Observatory will be planned in the afternoon of Nov. 9 (Thu).
Fee: 1,000 yen.
The participants will travel there by two buses (limit 40 seats).
The buses will leave the conference venue at 14:00 on 9 Nov (Thu) after taking
group photo. So please be sure to stay the venue of group photo.
On the 9 Nov (Thu), the passenger lists for each bus will be displayed at thereception desk. Please check the list to confirm on which bus you will be
riding and be sure to get on that bus. At Kwasan Obs., participants will be divided
into two groups and be taken on a tour around telescopes. All the passengers on
the same bus will be treated as a single group.
There will be NO space to put large luggage on the buses for the excursion.
In addition, after the excursion, the buses will go directly to ‘Ganko Takasegawa
Nijoen’, without returning to the conference venue.
Please do not bring large luggage to the conference venue on that day.

BanquetBanquet will be held in the evening of Nov. 9 (Thu) at the ‘Ganko Takasegawa
Nijoen’ at 18:30-21:00.
Place: Ganko Takasegawa Nijoen
Address:
484-6, Higashi Namasu-cho,Nijo-kudaru, Kiyamachi-dori,
Nakagyo-ku, Kyoto
Tel: 075-223-3456
Fee: 7,000 yen.

APSPM-2017 Meeting
7 November(Tuesday)
Chair

Time
9:00
9:30-9:45

Takashi
SakuraiPresenterKazunari Shibata

Session1: Progress on instrumentation and future plans
9:45-10:10
Thomas Rimmele
Progress and perspective of the DKIST
invitedO1_001I
10:10-10:25 Kiyoshi Ichimoto
Progress in Solar Observing Instrumentation at Hida Observatory
contributed O1_002
10:25-10:40 Stanislav Gunar
Quiescent Prominences in the Era of ALMA: Kinetic Temperature Diagnostics
contributed O1_003
10:40-10:55

Wenda
Cao

Title
Registration
Opening

Coffee break

Session1: Progress on instrumentation and future plans
10:55-11:20 Kyungsuk CHO
Toward Next Generation Coronagraph: Development of Compact Diagnostic
invitedO1_004I Coronagraph on ISS
11:20-11:45 Weiqun Gan
Advanced Space-based Solar Observatory: Progress and Prospect
invitedO1_005I
11:45-12:00 Hui Li
The Lyman-alpha Solar Telescope (LST): Status and Update
contributed O1_006
12:00-12:15 Carlos Quintero Noda
Chromospheric polarimetry through multi-line observations of the 770 and 850
nm spectral regions
contributed O1_007
12:15-12:30 Haosheng Lin
Instrumentation for Solar Physics from Cubesat and Small Satellites
contributed O1_008
12:30-14:00

Lunch

Session1: Progress on instrumentation and future plans
14:00-14:25 Dipankar Banerjee
Science with India's space mission Aditya L1
invitedO1_009I
Session2: MHD processes in photosphere, chromosphere and corona
Yoshinori 14:25-15:00
Suematsu
15:00-15:15
15:15-15:30

15:30-16:45

Shadia Habbal
keynoteO2_010K
Paul Cally
contributed O2_011
Elena Kupriyanova
contributed O2_012

plasma physics in corona and solar wind
Hidden Alfvénic Energy in the Solar Atmosphere
A role of the co-phased quasi-periodic pulsations in the energy release of the
weak solar flare
Poster & Coffee break

Session2: MHD processes in photosphere, chromosphere and corona
16:45-17:10 Shin TORIUMI
Physical Processes of Flux Emergence and Active Region Formation
invitedO2_013I
17:10-17:25 Hui Tian
Jongchul
Two types of surge-like activities above sunspot light bridges
contributed O2_015
Chae
17:25-17:40 Shahin Jafarzadeh
Slender Ca II H Fibrils in the Low Solar Chromosphere
contributed O2_016
17:40-17:55 Kumi Hirose
Statistical study of small blue shifted events
contributed O2_017

8 November(Wednesday)
Chair

Time

Presenter

Title

Session4: Solar interior and activity cycle of the Sun and stars
9:30-10:05
Yasuo Takeuchi
Solar neutrino measurements at Super-Kamiokande
keynoteO4_020K
Arnab R.
10:05-10:30 Hideyuki Hotta
Choudhuri
Recent development of solar dynamo model
invitedO4_021I
10:30-10:45 Sarah Jabbari
Formation of dynamo-driven bipolar magnetic spots in stratified turbulence
contributed O4_047
10:45-11:00

Coffee BreakSession2: MHD processes in photosphere, chromosphere and corona
11:00-11:35 Mark Cheung
Using Radiative MHD Simulations and SDO/AIA to Study the Thermal
keynoteO2_018K Structure and Evolution of Solar Flares
ChiaSession3: Flare, ejection and space weather
Hsien Lin 11:35-12:00 Piyali Chatterjee
Modeling Repeatedly Flaring δ Sunspots
invitedO3_022I
12:00-12:15 Mingde Ding
Spectral features of an X-shaped flare as implications for energy release anddynamics in the flare atmosphere
contributed O3_023
12:15-14:00

Lunch

Session3: Flare, ejection and space weather
14:00-14:35 Haimin WangHigh Resolution Flare Observations with the 1.6 m NST at BBSO
keynoteO3_024K
14:35-14:50 Akiko Tei
Blue asymmetry of the chromospheric Mg II lines in a solar flarecontributed O3_025
Kiyoshi
14:50-15:05 Yu-Lun Liou
Analysis of Hard X-ray and Microwave Observations with Fokker-Planck
Ichimoto
Model in Solar Flares
contributed O3_026
15:05-15:20 Yuri Litvinenko
Models of diffusive and nondiffusive transport of solar energetic particles
contributed O3_027
15:20-15:35 David Tsiklauri
Particle-In-Cell, fully kinetic scale modelling of solar radio bursts
contributed O3_028
15:35-16:30

Poster & Coffee BreakSession3: Flare, ejection and space weather
16:30-17:05 Nat Gopalswamy
CME kinematics and geo effectivenesskeynoteO3_029K
17:05-17:20 Zigong Xu
Observations of the CME shocks and the production of SEPs
Youngcontributed O3_030
deuk Park 17:20-17:35 Hsiu-Shan Yu
The dynamic character of the solar wind, and its implications for Solar Probe
Plus and Solar Orbiter
contributed O3_031
Session1: Progress on instrumentation and future plans
17:35-18:00 Toshifumi Shimizu
Future plans of Japanese space solar missions
invitedO1_032I

9 November (Thursday)
Chair

Time

HiroakiIsobePresenter

Title

Session3: Flare, ejection and space weather
9:30-10:05
Kanya Kusano
Project for Solar-Telestorial Environment Prediction (PSTEP)
keynoteO3_033K
10:05-10:30 Yong-Jae Moon
Development of space weather forecast models based on statistics and deepinvited
O3_034I learning methods
10:30-10:45 Rok-Soon Kim
Space weather forecast using background information generated by superposed
observations over previous Carrington cycles
contributed O3_035
10:45-11:00 Susanta Bisoi
Evidence of electron cyclotron maser emission at decimetric frequency: Firsthigh cadence GMRT observations
contributed O3_036
11:00-11:15 Masumi Shimojo
The First ALMA Observation of a Solar Plasmoid Ejection from an X-Ray
Bright Point
contributed O3_037
11:15-11:30 Jeongwoo Lee
Sigmoidal Hot Channel Before Solar Eruptions
contributed O3_038
11:30-12:50

12:50-13:00
Kazunari
13:00-13:40
ShibataLunch
APSPM Young Career Award
Pengfei Chen
Coronal EIT waves: A story of Twenty Years
YCA lecture YCA_039

13:40-14:00

Group Photo

14:00-17:30

Excursion (Kwasan Observatory)

18:30-21:00

Banquet (Ganko Takasegawa Nijoen)

10 November (Friday)
Chair

MingdeDing

Time
Presenter
Title
Session3: Flare, ejection and space weather
9:30-9:55
Daisaku Nogami
Superflares on solar-type stars
invitedO3_040I
9:55-10:10
Yuta Notsu
Spectroscopic observations of solar-type superflare stars
contributed O3_041
10:10-10:25 Kosuke Namekata
Statistical Study of Solar White-light Flares and Comparisons with Superflares
on Solar-type Stars
contributed O3_042
10:25-10:50 Petr Heinzel
Continuum emission from solar flares
contributed O3_043
10:50-11:05

Break

Session4: Solar interior and activity cycle of the Sun and stars
11:05-11:40 Jie Jiang
Flux transport dynamo and solar cycle
keynoteO4_044K
Paul Cally 11:40-11:55 Gopal Hazra
A theoretical model of the variation of the meridional circulation with the solar
cycle
contributed O4_045
11:55-12:10 Chia-Hsien Lin
Probing magnetic fields in the solar convection zone with solar-cycle variationsof meridional flows
contributed O4_046
12:10-13:30

Ayumi
Asai

Lunch

Session2: MHD processes in photosphere, chromosphere and corona
13:30-13:55 Tetsuya MAGARA
Flux-Emergence Model for the Characterization of Solar Active Regions
invitedO2_019I
13:55-14:10 Takaaki Yokoyama
ALMA observations of the solar chromosphere on the polar limb
contributed O2_048
Session4: Solar interior and activity cycle of the Sun and stars
14:10-14:35 Dean-Yi Chou
Interaction Between Acoustic Waves and Sunspots
invitedO4_049I
14:35-15:00 Junwei Zhao
Studying Solar Interior and Higher Atmosphere using Helioseismic Waves
invitedO4_050I
15:00-15:15 Arnab Choudhuri
3D Kinematic Model of the Solar Flux Transport Dynamo
contributed O4_051
15:15-15:45 Kiyoshi Ichimoto
Closing Remarks, Award, Remark from SOC-Chair of the 5th APSPM, Closing

List of Poster
Session1: Progress on instrumentation and future plans
ID
Presenter
Title
P1_ 001 Ming

Xiong

Prospective Out-of-ecliptic White-light Imaging of Interplanetary Corotating Interaction Regions at Solar Maximum

P1_ 002 Tetsu

Anan

Developments of multi-lines spectro-polarimeter of the Domeless Solar Telescope at Hida Observatory

P1_ 003 Su-Chan

Bong

2017 Total Solar Eclipse Expedition of KASI

P1_ 004 Masaoki

HaginoCoronal green line observation at the Lijiang Station of Yunnan Observatory

P1_ 005 Agustinus

Admiranto Preliminary Study on Solar Observing Facility in Timau National Observatory

P1_ 006 Zhi

Xu

Introduction of the New Vacuum Solar Telescope of China

P1_ 007 Natsuki

Tsuda

Observation of Solar Radio Bursts by CALLISTO Radio Spectrometer in Ibaraki University

P1_ 008 N.N.M.

Shariff

Sunspots Monitoring Using a Small Telescope at Universiti Teknologi MARA

Session2: MHD processes in photosphere, chromosphere and corona
ID
Presenter
Title
P2_ 010 Kiyoto

Shibasaki

Magnetic moment of thermal plasma and activities in the solar atmosphere

P2_ 011 Yikang

Wang

Effect of radiative loss on waves in chromosphere

P2_ 012 Daniela

LacatusComparative studies of the quiet sun under different conditions: in a coronal hole, under a magnetic canopy, and“pure” quiet sun

P2_ 013 David

TsiklauriAlfven wave phase-mixing in flows: why over-dense solar coronal open magnetic field structures are cool?

P2_ 014 Chia-Hsien

Lin

Solar Cycle Variation of Open Magnetic Flux Regions

P2_ 015 Rahul

Yadav

Stokes Profile Inversion code for the Photospheric spectral line

P2_ 016 Shota

Ninomiya

Statistical analysis of formation of solar magnetic flux tube with kilogauss magnetic field strengthP2_ 017 Jingwen

Zhang

Dark knots in a penumbral intrusion into a sunspot umbra

P2_ 018 Kyuhyoun

ChoOrigin of three minute oscillations in a sunspot umbra

P2_ 019 DongukSong

Three-minute Sunspot Oscillations Driven by Magnetic Reconnection in a Light Bridge

P2_ 020 Tanmoy

Samanta

Study of supersonic downflow at the transition region above sunspots

P2_ 021 Juhyeong

Kang

Foot point Brightening at near pore boundaryP2_ 022 Debi Prasad Choudhary Flows along the Super-Penumbral Fibrils in Sunspots
P2_ 023 PriyaTG

Emergence of running penumbral waves in the sunspots

P2_ 024 Hannah

Kwak

Velocity oscillations in the chromosphere and transition region above plage region

P2_ 025 Minju

Seo

Analysis of Ellerman Bomb Spectra Observed by FISS

P2_ 026 Satomi

TokudaObservation of Fine Scale Dynamics in the Solar Chromosphere with a Dual Camera Imaging System

P2_ 027 Yoshinori

Suematsu

High Resolution Observations of Spicules in Upper-Photospheric Lines

P2_ 028 M.

YoshidaWave Propagation on Spicules Observed by Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP)

P2_ 029 Yamini K.

Rao

Driving process for highly impulsive plasma outflows

P2_ 030 Takako

Ishii

H-alpha surges at the emerging flux region observed before the pore formation (NOAA 12660)

P2_ 031 Qingmin

Zhang

Large-amplitude prominence oscillations: observations and numerical simulations

P2_ 032 Keisuke

NishidaThe Role of a Flux Rope Ejection in a Three-dimensional Magnetohydrodynamic Simulation of a Solar Flare

P2_ 033 Yuhao

Zhou

Three-dimensional MHD simulation of solar prominence oscillations in a magnetic flux rope

P2_ 034 Aki

MachidaDetermination of the wave property in the quiescent prominence from the phase difference

P2_ 035 Sanetaka

Okada

Temperature diagnosis of Solar prominences with a simultaneous observation of H-alpha, H-beta
and Ca8542A lines

P2_ 036 Y.

Hanaoka

Statistical Study of the Magnetic Field in Solar Filaments

P2_ 037 Yuwei

Huang

H-alpha absorption profile of erupting filament

P2_ 038 Heesu

Yang

Observation of the Streaming-Kink Instability in the Solar Prominence

P2_ 039 Denis

CabezasDoppler Characteristics and Dynamics Processes of the Moreton Wave on 2014 March 29

Session3: Flare, ejection and space weather
ID
Presenter
Title
P3_ 040 Xiaoli

Yan

Recent scientific results of 1 m New vacuum solar telescope at Fuxian Lake Observatory

P3_ 041 Ahmed

Ibrahim

The FMT at KSU as part of the CHAIN project with preliminary results

P3_ 042 Qi

Hao

A Circular White-Light Flare with Impulsive and Gradual White-Light Sources

P3_ 043 YongliangSongA white-light flare triggered by flux emergence in NOAA active region 11476

P3_ 044 Satoshi

MasudaCold Solar Flares Observed with Nobeyama RadioheliographP3_ 045 Ze

Zhong

The transition from circular to nonstandard two-ribbon flares due to magnetic flux ropes bifurcation

P3_ 046 Dong

Li

Explosive Chromospheric Evaporation Driven by Nonthermal Electrons around One Footpoint of a Solar Flare Loop

P3_ 047 Yu

Chen

Case study of chromospheric evaporation at flare ribbons by IRIS

P3_ 048 Yun-Chen

Yang

APPARENT MOTION OF FLARING RIBBONS OBSERVED BY SDO/AIA

P3_ 049 Kyoung-Sun Lee

Spectroscopic observation of a loop-top source of an M1.3 limb solar flare

P3_ 050 Yuandeng

Shen

Observational Analysis of the Fine Structure and Formation of Solar Jets

P3_ 051 Chloe

Pugh

Properties of quasi-periodic pulsations in solar flares from a single active region

P3_ 052 Lilis

Mubasaroh

P3_ 053 Takahito

SakaueEmergence Process of the Satellite Spots Leading to the Successive Flares

P3_ 054 Shin'ichi

NagataOn the relationship between the rapid penbumbra formation and impulsive flare in NOAA12403

P3_ 055 Herna

Fahriyah

Evolution of Coronal Jets on the Solar Limb based on SDO/AIA Images Datas

P3_ 056 JinchengWang

The formation of an active-region filament: the material by jets

P3_ 057 Alin

Paraschiv

Recurrent Active region coronal jets: Examining the magnetic configuration of a persistent jet inducing micro-flaresite

P3_ 058 Huaning

Wang

Type of magnetic null point and filament in the solar atmosphere

P3_ 059 Rui

LiuMagnetic Flux Rope: Topology and Twist Profile

Analysis of Sunspot Proper Motion related to X-Class Solar FlareP3_ 060 Daikichi

Seki

Increase in the amplitude of Line-of-sight velocities of the small-scale motions in a solar filament before eruption

P3_ 061 Kenichi

Otsuji

Rapid eruptive phenomena observed by SMART/SDDI and its influence to the interplanetary space

P3_ 062 Navin

Joshi

Investigation of a Large Ejective Solar Eruption from a Typical Coronal-Jet-Base Field Configuration

P3_ 063 David

TsiklauriElectron plasma wake field acceleration in solar coronal and chromospheric plasmas

P3_ 064 Keiji

Hayashi

MHD simulation of solar active region driven byobservation-inferred plasma motion and electric fieldP3_ 065 Jie

Hong

RADYN simulations of non-thermal and thermal models of Ellerman bombs

P3_ 066 Tangmu

Li

2.5D Particle-in-cell Simulation of Solar type III radio bursts

P3_ 067 WenjunDing

2.5 D particle-in-cell to simulate Coronal Particle Acceleration of HeG3 / 4

P3_ 068 JihyeKang

P3_ 069 Jongchul

Chae

P3_ 070 AnandJoshi

P3_ 071 Ryoya

UemuraStatistical Study of Active-region Microflares Observed with Hinode/XRT

P3_ 072 Ya-Hui

Yang

Flare Productivity in Different Magnetic Types of Active Regions

P3_ 073 Harim

Lee

Statistical study on the radial and azimuthal wave modes of 24 Halo Coronal Mass Ejections using multi spacecraft

P3_ 074 Subhash

Kaushik

Transient Plasma Signatures and Space Weather

P3_ 075 Eunsu

Park

Solar Flare Forecast Model based on Convolutional Neural Network using SOHO MDI Data and its Optimizations

P3_ 076 Daye

Lim

Forecast of Solar Major Flare Occurrence Rates Based on Vector Magnetic Parameters Using SDO/HMI Data

P3_ 077 Naoto

Nishizuka

Flare Forecast using Machine-learning of Multi-wavelength Observations of Active Regions

P3_ 078 Kangwoo

Yi

Flare Occurrence Prediction based on Convolution Neural Network and Comparison with Previous Models

P3_ 079 Hiroyuki

MaeharaStarspot activity and superflares on solar-type stars

P3_ 080 Abbas

RaboonikPrediction of Solar Flares Using Unique Signatures of Magnetic Field Images

P3_ 081 Dongmin

Ryu

P3_ 093

Zety
Sharizat bt

Hamidi

Relationship between the Occurrence of a Flare and the Small-Scale Variation of Photospheric Magnetic Field in
Active Region 12371
Evidence for a Magnetic Reconnection Origin of Plasma Outflows along Post-CME Rays
Pre-eruption Oscillations in Quiescent Filament

Solar particle event statistical model comparison for Korean Pathfinder Lunar Orbiter mission
The Observation of Heart-shape Active Region 2529 Producing Strong M6.7 class Solar Flare and Gradual Coronal
Mass Ejections on 18th of April 2016

Session4: Solar interior and activity cycle of the Sun and stars
ID
Presenter
Title
P4_ 082 Masumi

Shimojo

Variation of Solar Microwave Spectrum in Last Half Century

P4_ 083 Sudip

MandalOverview of the science results obtained from Kodaikanal digitizeddata archive: white-light and Ca-K

P4_ 084 Makoto

Hasegawa

Search for periodic modulations of the solar neutrino flux in Super-Kamiokande

P4_ 085 Satoru

UeNo

Development of data-archives of solar chromospheric full-disk images and researches on long-term variations ofsolar activities and the earth’s upper atmosphere

P4_ 086 Chuan

Li

Waiting time distributions of solar and stellar activities: Poisson process or with memory?

P4_ 087 Kyeore

Lee

Shock Merging in the Chromosphere of Sunspots

P4_ 088 Ganghua

Lin

Data Processing for Multiple Solar Activity Cycles

P4_ 089 Shota

Arai

Influence of strong viscosity on convective energy transport

P4_ 090 Alina

Donea

P4_ 091 K.

Kuzanyan

P4_ 092 Ryuji

MinetaStudies on the acoustic directionality of solar flare-induced quakes
Merging Mosaics and Super-Mosaics of High Resolution Vector Magnetic Field Maps for Studies of Spatial Spectraof Solar Magnetic Field and Helicity
Construction of a mean field model of the convection zone with turbulence transport coefficients parameterization
based on 3D global simulations

APSPM 2017

YCA lecture

13

APSPM 2017

Coronal EIT waves: A story of Twenty Years
Abstract Author(s): Pengfei Chen
Institution(s): Nanjing University
Presentation: YCA 039
Abstract
Coronal EIT waves are a large-scale wavelike phenomenon, which was first observed by the Extreme-Ultraviolet Imaging Telescope (EIT) in 1997. Therefore,
this year marks the 20th anniversary of the great discovery, which was initiallynamed “EIT wave” after the telescope. Such a spectacular phenomenon sparked
long-lasting interest and debates. The debates were concentrated on two topics, one is about the driving source, and the other is about its nature. While
it is now widely accepted that EIT waves are driven by mass ejections rather
than by the pressure pulse in solar flares, the interpretation of EIT waves isstill controversial. The fast-mode MHD wave model, which is believed by manycolleagues, is confronted with many observational discrepancies. Fifteen years
ago, we proposed that EIT waves are an apparent propagation due to successive
stretching of magnetic field lines in order to explain why EIT waves are generally 3 times slower than the fast-mode waves in the corona. In this talk, I will
explicate how this model matches well with the new observations from the Solar
Dynamics Observatory and how the model is updated with new observationalfeatures.

14

APSPM 2017

Session 1
Progress on instrumentation and future plans

15

APSPM 2017
Session 1: Progress on instrumentation and future plans

Status of the Daniel K. Inouye Solar Telescope
Abstract Author(s): Thomas Rimmele (Valentı́n Martı́nez Pillet) and the
DKIST Team
Institution(s): National Solar Observatory
Presentation: O1 001I
Abstract
The construction of the 4m Daniel K. Inouye Solar Telescope (DKIST) on
Haleakala, Maui is progressing on schedule. The construction is 80% complete. Operations are scheduled to begin early 2020. DKIST will replace the
NSO facilities on Kitt Peak and Sac Peak with the worlds largest solar telescope. DKIST was designed to meet the needs of critical high resolution andhigh sensitivity spectral and polarimetric observations of the sun. DKIST’s
superb resolution and polarimetric sensitivity will enable astronomers to unravel many of the mysteries the Sun. The design allows DKIST to operate asa coronagraph at infrared wavelengths where the sky background is low andbright coronal emission lines are available. Taking advantage of its large aperture and infrared polarimeters DKIST will be capable to routinely measure thecurrently illusive coronal magnetic fields. The state-of-the-art adaptive optics
system provides diﬀraction limited imaging and the ability to resolve featuresapproximately 20 km on the Sun. Five first light instruments will be available
at the start of operations. The data from these instruments will be distributed
to the community via the NSO/DKIST data center. We provide an overview ofthe facility and discuss the project status.

16

APSPM 2017
Session 1: Progress on instrumentation and future plans

Progress in Solar Observing Instrumentation at Hida
Observatory
Abstract Author(s): Kiyoshi Ichimoto, Hida Observatory teamInstitution(s): Kyoto University
Presentation: O1 002
Abstract
Hida observatory has two advanced solar telescopes, i.e., the Domeless Solar
Telescope (DST) and the Solar Magnetic Activity Research Telescope (SMART).
The DST is a 60cm aperture vacuum telescope equipped with high dispersion
spectrometers, and aims at precise observations in high spatial and spectral resolution. The SMART is a set of refractive telescopes with apertures of 20cm
and 25cm, and aims at a regular basis observation in wide fields of view tocapture flares and filament eruptions and, by which, to contribute to the space
weather study. Recently we have installed a new adaptive optics system anda multi-wavelength spectro-polarimeter on DST, and a high cadence full disk
Doppler imaging system and a total solar spectral monitor on SMART. We
will present some details of these advanced instruments that have started forproviding unique dataset for solar research.

17

APSPM 2017
Session 1: Progress on instrumentation and future plans

Quiescent Prominences in the Era of ALMA: Kinetic
Temperature Diagnostics
Abstract Author(s): Stanislav Gunar, P. Heinzel, U. Anzer, D. Mackay, M.
Barta, I. Skokic
Institution(s): Astronomical Institute of the Czech Academy of Sciences, MaxPlanck Institute for Astrophysics, University of St Andrews
Presentation: O1 003
Abstract
We provide the theoretical background for the analysis of the ALMA prominence
observations and the diagnostics of the prominence plasma kinetic temperature.
To do this we employ the 3D whole-prominence fine structure model which
provides us with the synthetic ALMA-like observations of a complex simulated
prominence. We use such synthetic observations as if these were a pair of actual ALMA observations, where in one the prominence is optically thin andin the other optically thick. This allows us to develop a technique that canbe used for the accurate analysis of the prominence plasma thermal properties
from such a pair of simultaneous ALMA observations. In addition to the synthetic observations, the used 3D model oﬀers detailed information about theproperties of the simulated plasma distributed along any line of sight (such as
kinetic temperature and the optical thickness). This allows us to assess theaccuracy of the developed technique and its results. We also briefly present theEuropean ALMA Regional Center (EU ARC), namely its Czech node locatedat the Astronomical Institute of the Czech Academy of Sciences. This node has
Europe-wide unique expertise in solar research with ALMA. Finally, we oﬀer an
overview of the recent Science Verification solar ALMA observations acquired by
the international Solar ALMA ObsMode Development Team with participationof the Czech ARC node astronomers.

18

APSPM 2017
Session 1: Progress on instrumentation and future plans

Toward Next Generation Coronagraph: Development ofCompact Diagnostic Coronagraph on ISS
Abstract Author(s): Kyungsuk Cho
Institution(s): Korea Astronomy and Space Science Institute
Presentation: O1 004I
Abstract
The Korea Astronomy and Space Science Institute plans to develop a coronagraph in collaboration with National Aeronautics and Space Administration(NASA) and install it on the International Space Station (ISS). The coronagraph is an externally occulted one stage coronagraph with a field of view from
2.5 to 15 solar radii. The observation wavelength is approximately 400 nm
where strong Fraunhofer absorption lines from the photosphere are scattered bycoronal electrons. Photometric filter observation around this band enables theestimation of 2D electron temperature and electron velocity distribution in thecorona. Together with the high time cadence (< 12 min) of corona images todetermine the geometric and kinematic parameters of coronal mass ejections,the coronagraph will yield the spatial distribution of electron density by measuring the polarized brightness. For the purpose of technical demonstration,
we intend to observe the total solar eclipse in 2017 August for the filter systemand to perform a stratospheric balloon experiment in 2019 for the engineeringmodel of the coronagraph. The coronagraph is planned to be installed on the
ISS in 2021 for addressing a number of questions (e.g. coronal heating and solar
wind acceleration) that are both fundamental and practically important in thephysics of the solar corona and of the heliosphere.

19

APSPM 2017
Session 1: Progress on instrumentation and future plans

Advanced Space-based Solar Observatory: Progress andProspect
Abstract Author(s): Weiqun Gan, ASO-S teamInstitution(s): Purple Mountain Observatory
Presentation: O1 005I
Abstract
ASO-S (Advanced Space-based Solar Observatory) is a mission proposed for the
25th solar maximum by the Chinese solar community. Its scientific objectives
aim at the relationships among solar magnetic field, solar flares, and coronalmass ejections. By September. 2017, ASO-S fulfilled all the procedures to bean established approval project. This talk describes in brief the progress of
ASO-S and the prospect in near future.

20

APSPM 2017
Session 1: Progress on instrumentation and future plans

The Lyman-alpha Solar Telescope (LST): Status andUpdateAbstract Author(s): Hui Li, the LST teamInstitution(s): Purple Mountain Observatory
Presentation: O1 006
Abstract
The Lyman-alpha Solar Telescope (LST) is one of the three payloads of the
proposed Advanced Space-based Solar Observatory (ASO-S), which is composedof a Solar Disk Imager (SDI) with an aperture of 60 mm, a Solar Corona Imager(SCI) also with an aperture of 60 mm and a White-light Solar Telescope (WST)with an aperture of 80 mm. The SDI is to image the Sun from the disk center to
1.2 solar radii in the Lyman-alpha waveband (121.6±7.5nm) with a cadence of3 - 12s. and a pixel resolution is 0.56”. The SCI uses a 2k by 2k CCD camera to
image the inner solar corona from 1.1 to 2.5 solar radii with a cadence of 3 - 120s
in both the Lyman-alpha waveband (121.6±10nm) and white-light (700±20nm).
The WST is design to image the Sun in violet narrow-band continuum (360±2.0nm) from the disk center to 1.2 solar radii with a general cadence of 3 - 12s (itcan be as high as 0.2s in the fast event mode). In this talk, I will introduce the
LST instrument, its preliminary design, current status and updates.

21

APSPM 2017
Session 1: Progress on instrumentation and future plans

Chromospheric polarimetry through multi-line
observations of the 770 and 850 nm spectral regions
Abstract Author(s): Carlos Quintero Noda, Yukio Katsukawa, Masahito Kubo,
Toshifumi Shimizu, the Sunrise/SCIP Team.
Institution(s): Japan Aerospace Exploration Agency, National Astronomical
Observatory of Japan
Presentation: O1 007
Abstract
Sunrise Chromospheric Infrared Polarimeter is an international instrument under development for the third flight of the Sunrise balloon, scheduled for 2020.
It aims to ascertain the magnetic field topology and the physical properties ofdynamics events in the lower atmosphere. The instrument will observe multiple
spectral lines at two spectral regions, i.e. 770 and 850 nm, where we can findZeeman sensitive photospheric lines, the upper photospheric K I D1 and D2,
and the chromospheric Ca II infrared lines. In addition, although some of thementioned lines have been observed before, most of them are new candidates forsolar observations. In this regard, we study the characteristics of those lines examining their sensitivity to perturbations on several physical parameters, theirheight of formation, and the maximum polarization signals they produce. The
first results, presented in Quintero Noda et al. (2016, 2017a,b), show that the
spectral lines are sensitive to changes in the atmospheric parameters in a rangeof heights that cover the photosphere and the middle chromosphere. Therefore,
observing multiple lines, allows simultaneously covering various atmosphericlayers, what brings the possibility of expanding our knowledge of the Sun andunravelling the properties of the chromospheric magnetic field.

22

APSPM 2017
Session 1: Progress on instrumentation and future plans

Instrumentation for Solar Physics from Cubesat andSmall Satellites
Abstract Author(s): Haosheng Lin
Institution(s): University of Hawaii
Presentation: O1 008
Abstract
The rapid advancement of cubesat and small satellites technologies oﬀers new
low-cost space access opportunities for solar physics research. However, thestringent size limitations of small satellites is a formidable challenge to instrument design that have intrinsic requirement for the aperture size of the telescope.
New optical designs are needed to reduce the volume of the optical system without compromising the optical performance of the instrument. This paper will
present optical designs for compact large-field, multi-slit, multi-channel disk
and coronal spectropolarimeters for deployment by cubesat and small satellite
platforms.

23

APSPM 2017
Session 1: Progress on instrumentation and future plans

Science with India’s space mission Aditya L1
Abstract Author(s): Dipankar Banerjee
Institution(s): Indian Institute of Astrophysics
Presentation: O1 009I
Abstract
Aditya-L1 is India’s first dedicated scientific mission to study the sun. AdityaL1 mission will be inserted in a halo orbit around the L1, which is 1.5 million
km from the Earth. The satellite will be launched around 2020 by PSLV-XL
from Sriharikota, India. It will carry seven payloads which will provide observations of Sun’s Photosphere, Chromosphere (NUV) and corona (Visible, softand hard X-ray and NIR). In addition, particle payloads will study the particle
flux emanating from the Sun and reaching the L1 orbit, and the magnetometer
payload will measure the variation in magnetic field strength at the halo orbit
around L1. In this talk I will give an overview of the diﬀerent payloads and its
science objectives. Plans for co-ordinated observations with other ground andspace based facilities will be discussed.

24

APSPM 2017
Session 1: Progress on instrumentation and future plans

Studies for next generation solar physic mission
Abstract Author(s): Toshifumi Shimizu
Institution(s): Japan Aerospace Exploration Agency
Presentation: O1 032I
Abstract
In 2016, an advisory team for next generation solar physics mission (NGSPM’s
Science Objectives Team) was formed with 14 members appointed by NASA,
JAXA, and ESA as a means of improving international coordination in solar
physics and developing a multilateral solar physics mission concept for the next
decade. This is likely to be realized as a Japan-led mission launched after 2024,with substantial contributions from the United States and Europe. In the teamstudy, we developed and documented scientific objectives in the field of solar
physics and priorities for an NGSP mission, within the resources and framework by the three agencies. Specific sub-objectives and essential observationaltasks were identified in three top-level science objectives, i.e., 1) Formation
mechanisms of the hot and dynamic outer solar atmosphere, 2) Mechanisms oflarge-scale solar eruptions and foundations for predictions, and 3) Mechanisms
driving the solar cycle and irradiance variation. There are two broad avenues,
both with distinct merits, for future research: physical mechanisms on elemental(small) scales, versus global processes aﬀecting/involving large fractions of thesolar interior and/or atmosphere. With the resources available for a NGSPM
on the timescale of the next decade, the team recommends the study of fundamental physical processes at high spatial and temporal resolution through alltemperature regimes of the solar atmosphere. For this study, the SOT identified a minimum set of instruments with which NGSPM can address the greatest
number of sub-objectives and maximize the science return of the mission. The
Japanese solar physics community makes eﬀorts to realize a part of such instruments in the middle of the next decade. The other avenue requiring global,
multi-vantage observations would be one of the path for the decades after 2030’s,
because they require strategic preparation of technologies and large resources.
The NGSPM Science Objectives Team final report submitted to the agencies
is used at various occasions, such as to propose the missions and to coordinate
international collaborations.

25

APSPM 2017
Session 1: Progress on instrumentation and future plans

Prospective Out-of-ecliptic White-light Imaging ofInterplanetary Corotating Interaction Regions at Solar
Maximum
Abstract Author(s): Ming Xiong, Jackie A. Davies, Bo Li, Liping Yang, Ying
D. Liu, Lidong Xia, Richard A. Harrison, Hayashi Keiji, Huichao Li
Institution(s): National Space Science Center, Rutherford Appleton Laboratory Space, Shandong University, HIT Institute of Space Science andApplied Technology, University of Chinese Academy of Sciences, Nagoya
University
Presentation: P1 001
Abstract
Interplanetary corotating interaction regions (CIRs) can be remotely imaged
in white light (WL), as demonstrated by the Heliospheric Imagers (HIs) on
board the STEREO spacecraft. Because of the in-ecliptic locations of both the
STEREO spacecraft, the longitudinal dimension of interplanetary CIRs has, up
to now, always been integrated in WL imagery. To synthesize the WL radiance patterns of CIRs from an out-of-ecliptic (OOE) vantage point, we performforward magnetohydrodynamic modeling of the 3D inner heliosphere at solar
maximum. The mixing eﬀects associated with viewing 3D CIRs are significantly
minimized from an OOE viewpoint. Our forward modeling results demonstratethat OOE WL imaging from a latitude greater than 60 can (1) enable thegarden-hose spiral morphology of CIRs to be readily resolved, (2) enable multiple coexisting CIRs to be diﬀerentiated, and (3) enable the continuous tracing of
any interplanetary CIR back toward its coronal source. In particular, an OOEview in WL can reveal where nascent CIRs are formed in the extended coronaand how these CIRs develop in interplanetary space. Therefore, a panoramicview from a suite of wide-field WL imagers in a solar polar orbit would beinvaluable in unambiguously resolving the large-scale longitudinal structure of
CIRs in the 3D inner heliosphere.

26

APSPM 2017
Session 1: Progress on instrumentation and future plans

Developments of multi-lines spectro-polarimeter of theDomeless Solar Telescope at Hida Observatory
Abstract Author(s): Tetsu Anan, Yu Wei Huang, Yoshikazu Nakatani, Kiyoshi
Ichimoto, Satoru Ueno, Goichi KimuraInstitution(s): Kyoto University
Presentation: P1 002
Abstract
Multi-lines spectro-polarimetry enables us to diagnose structures of magnetic
field vectors along the line of sight, or develop new diagnoses of other anisotropies
in the solar atmosphere, for examples, electric fields, radiations and collisions.
We developed a new spectro-polarimeter on the Domeless Solar Telescope at
Hida Observatory to obtain full Stokes spectra in multi-spectral windows simultaneously. The new polarimeter consists of a 60 cm aperture vacuum telescope,
an image rotator, a slit spectrograph, polarization modulator and analyzer composed of a continuously rotating waveplate whose retardation is nearly constantin 500 - 1100 nm and a polarimetric beam splitter located closely behind thefocus of the telescope, fast and large format CMOS cameras and an infrared
camera. The spectrograph allows us to obtain spectra in as many wavelength
windows as the number of cameras. We developed the polarization modulator
and the analyzer, and calibrated instrumental polarizations of the system.

27

APSPM 2017
Session 1: Progress on instrumentation and future plans

2017 Total Solar Eclipse Expedition of KASI
Abstract Author(s): Su-Chan Bong, Seonghwan Choi, Jihun Kim, Jongyeob
Park, Bi-Ho Jang, Young-Deuk Park, Kyung-Suk Cho, Kyuhyoun Cho,
Jongchul Chae
Institution(s): Korea Astronomy and Space Science Institute, Seoul National
University
Presentation: P1 003
Abstract
Korea Astronomy and Space Science Institute (KASI) plans to develop a coronagraph to measure the coronal electron density, temperature, and speed using
four diﬀerent filters around 400 nm, where strong Fraunhofer lines from thephotosphere are scattered by coronal electrons. During the total solar eclipse
occurring on August 21 across USA, KASI will organize an expedition team todemonstrate the coronagraph measurement scheme and the instrumental technology. The observation site is in Jackson Hole, Wyoming, USA. We plan tobuild two coronagraphs without occulter to improve signal to noise ratio. In
addition, images of white light corona, wide field background, and all sky areplanned to be taken with DSLR cameras. We will present the preliminary resultsof the expedition.

28

APSPM 2017
Session 1: Progress on instrumentation and future plans

Coronal green line observation at the Lijiang Station of
Yunnan Observatory
Abstract Author(s): Masaoki Hagino, Takashi Sakurai, Kazuya Shinoda, Yu
Liu, Tengfei Song, Xuefei Zhang, Mingyu Zhao, Zhong Liu, Kiyoshi Ichimoto, Goichi Kimura, Kanta Hamada, Isao Suzuki
Institution(s): National Astronomical Observatory of Japan , Yunnan Observatories, Kyoto University, Meisei University, Bunkyo Gakuin University
Presentation: P1 004
Abstract
A coronagraph and a filter instrument attached to it (Norikura Green Line
Imaging System: NOGIS), which observe the intensity and Doppler shift of thecoronal green line (Fe XIV 530.3 nm), had been used at the Norikura Solar Observatory/NAOJ still 2009. After the closure of Norikura Solar Observatory, thecoronagraph and the NOGIS instrument was relocated to the Lijiang Stationof the Yunnan Observatory of NAOC in November 2013 and the observationof the solar corona has been resumed. The name should then be changed to
YOGIS (Yunnan Observatory Green-line Imaging System). The YOGIS instrument can observe not only coronal plasma motions but also velocity fields. Suchobservations are important in researches on coronal heating, flares, coronal massejections and space weather. In this paper we will introduce the YOGIS instrument and discuss the continuity of coronal green-line data between Norikura
and Lijiang observations.

29

APSPM 2017
Session 1: Progress on instrumentation and future plans

Preliminary Study on Solar Observing Facility in Timau
National Observatory
Abstract Author(s): Agustinus Gunawan Admiranto, E. Sungging Mumpuni,
Dhani Herdiwijaya
Institution(s): Indonesian National Institute of Aeronautics and Space, Bandung Institute of Technology
Presentation: P1 005
Abstract
Solar physics research in Indonesia is mainly conducted in LAPAN and ITB/Bosscha
Observatory. Solar physics research in LAPAN is in line with Space Science Center mission to be the center of regional forecast and prediction system. In linewith this mission, solar physics research in LAPAN is on the study of sunspots,
flares, coronal mass ejection, and solar radio burst. In collaboration with several
institution (Bandung Institute of Technology, Nusa Cendana University, Nusa
Tenggara Province and Kupang municipality) LAPAN is planning a National
Obervatory in which the planned location is in the Mount Timau (elev. 1300 m
above sea level) near Kupang, East Nusa Tenggara, and some of the proposed
equipment are of solar physics equipment which are hopefully related to thesolar physics research in a broader context (not only in space weather related
fields), i.e. solar transient phenomena, solar fine structure, solar interior, coronal mass ejections, solar cycle phenomena, magnetohydrodynamics, dynamics
of solar chromosphere, and dynamics of solar magnetic field related with interplanetary magnetic field. Due to the broadness of the proposed field of research,
there are many steps of equipment proposals, and the first step is related withthe observations of sunspot proper motion and simultaneous multi-wavelength
observations for solar flare prediction in both photosphere and chromospherelayers. In this respect, the equipment proposed are telescope for full disk observations in continuum, telescopes for multi-wavelength partial disk observations,and solar imaging spectroscopy. All this are supported with a high performancecomputer for speckle multi-wavelength imaging and real-time image processing.

30

APSPM 2017
Session 1: Progress on instrumentation and future plans

Introduction of the New Vacuum Solar Telescope of China
Abstract Author(s): Zhi Xu
Institution(s): Yunnan Observatories
Presentation: P1 006
Abstract
The New Vacuum Solar Telescope (NVST) is a 1 meter vacuum solar telescopethat aims to observe the fine structures on the Sun. The main tasks of NVST
are high resolution imaging and spectral observations, including the measurements of solar magnetic field. It is located by the Fuxian Lake of southwest
China, where the seeing is good enough to perform high resolution observations. The instruments, including the multi-channel high resolution imaging
system and two vertical spectrometers are located either on a 6 meter rotatable
instrument platform or on the frames of the vertical hanging bracket below therotating platform. As one of the current large solar telescopes in the world,
NVST achieves its designed performance in terms of high resolution observations. Considering that it is located between Europe and America, NVST could
work in combination with other European and American large solar telescopes
to form a global high resolution observation network. In this presentation I will
introduce the salient features of the observation mode, data process and datarequirement of NVST.

31APSPM 2017
Session 1: Progress on instrumentation and future plans

Observation of Solar Radio Bursts by CALLISTO Radio
Spectrometer in Ibaraki University
Abstract Author(s): Natsuki Tsuda, Satoshi Nozawa, Kazumasa Iwai, Ema
WashidaInstitution(s): Ibaraki University
Presentation: P1 007
Abstract
A solar radio burst is defined as a sudden, rapid and intense variation in thesolar radio emission. Solar radio type-III bursts appear in the frequency range
between several kHz and several GHz, and they are characterized by a rapid
frequency drift from high to low. These radio waves are thought to be emitted
by high energy electron beams accelerated by solar flares. Therefore, observation of the type-III bursts is important in order to understand the generation
processes of high energy particles. The CALLISTO radio spectrometer is a solar radio receiver. We have developed a solar radio observation system using a
CALLISTO receiver with a log-periodic antenna in the Mito campus of Ibaraki
University. The CALLSITO is operated in the frequency range between 100 and
850MHz with 400 channels every 0.5 s. Our Ibaraki CALLISTO is joining theworldwide solar radio monitoring network (e-CALLISTO) which is led by ETH
Zurich. Several solar radio type-III bursts related with C and M class flares has
been observed on April and July, 2017. The time evolutions of the observed
radio bursts are quite similar to those of other observatories. From these data
analysis, high reliability of our Ibaraki-CALLISTO system has been shown.

32

APSPM 2017
Session 1: Progress on instrumentation and future plans

SUNSPOTS MONITORING USING A SMALLTELESCOPE AT UNIVERSITI TEKNOLOGI MARA
Abstract Author(s): N.N.M. Shariﬀ
Institution(s): Universiti Teknologi MARA
Presentation: P1 008
Abstract
Sunspot is an activity that occurs on photosphere of the Sun. Sometimes it
emits highly energetic sub-atomic particles into space. These particles can cause
damages on our electrical systems. We have experienced sunspot events thatbreak our communications links and disrupting the ionosphere (which we use topropagate radio signals in the High Frequency (HF) radio spectrum of 3 MHz-30
MHz) and also by causing power surges on electrical power lines that trip circuit
breakers. Therefore, sunspot is a very good indicator to measure the activenessof the Sun. By monitoring the sunspots, perhaps we can predict them and learn
more about its structure. Since this field is new in our faculty, therefore, we haveembark this research with a small optical telescope-Celestron 8 Edge HD. Datataken using Canon EOS 700D on daily basis, if weather permits. During theobservation, daily visitor/passer-by (who are interested to know) are around 1015 persons at set-up area (we do not have a proper observatory yet). Although
this research is just a small step compared to other research, we really hope
this research can contribute to solar research in terms of public awareness onscientific matters.

33

APSPM 2017

Session 2
MHD processes in photosphere, chromosphere and corona

34

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

New Insights into the Physics of the Corona and the Solar
Wind from Total Solar Eclipse Observations
Abstract Author(s): Shadia Rifai Habbal, Adalbert Ding, Miloslav Druckmueller
Institution(s): University of Hawaii, Technische Universitae, Institute for Technical Physics, Brno University of Technology
Presentation: O2 010K
Abstract
Most of the clues to the physical processes that heat the corona and accelerate the solar wind are embedded in the properties and behavior of minor ions,
namely elements heavier than alpha particles. These properties are manifested
in remote sensing observations of the corona and in-situ particle measurements
in interplanetary space. At present, there is an abundance of space-based instruments dedicated to solar and heliospheric observations. However, the fieldof view common to these instruments leaves an essential data gap where the gradients in plasma parameters are the steepest, including changes in the magnetic
field. At present, this gap can be covered only by total solar eclipse observations.
Furthermore, the visible wavelength range oﬀers unique diagnostic potential forinvestigations of the physics and thermodynamics of the corona. In this presentation, we will briefly review some of the currently established views on coronalheating and solar wind acceleration. We then present multi-wavelength imaging
and spectroscopic observations of the corona acquired over the past decade during total solar eclipses. Among the important empirical inferences from thesedata are the spatial distribution of coronal temperature, and the freeze-in distance of minor ions in the inner corona. We show how these inferences provide
new insights, as well as raise new questions, regarding the processes that control the outer solar atmosphere and the solar wind flow. In particular, we will
describe the central role that prominences seem to play in the dynamics andthermodynamics of coronal structures and the solar wind, from defining theelectron temperature distribution in the corona, to the generation of plasma
instabilities and coronal mass ejections.

35

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Hidden Alfvénic Energy in the Solar Atmosphere
Abstract Author(s): Paul Cally
Institution(s): Monash University
Presentation: O2 011
Abstract
When large-scale fast MHD waves from the solar interior enter the solar atmosphere dominated by flux tube structures, they partially turn into kink waves,which may be observed. However, modeling suggests that most of the incident
fast wave energy instead converts quickly to Alfvén waves, which are incompressive and fine-scale, and hence largely invisible. This leads us to suggest that
there are huge reserves of hidden or dark Alfvénic energy in the solar atmosphere. The observed kink waves are merely the tip of the iceberg. This energy
may be ample to heat the active corona.

36

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

A role of the co-phased quasi-periodic pulsations in theenergy release of the weak solar flare
Abstract Author(s): Elena Kupriyanova, Masuda Satoshi, Kashapova Larisa, Zhdanov Dmitry
Institution(s): Pulkovo Observatory, Nagoya University, ISTP SO RAN
Presentation: O2 012
Abstract
Quasi-periodic pulsations (QPPs) are usually observed during solar flares andthey carry an important information about processes of both energy release andenergy transfer. We present an analysis of unusual co-phased QPPs found in theemission of the weak GOES C class solar flare occurred at the eastern limb on
Dec 21, 2015. The revealed periods of QPPs are about 15 seconds. Moreover,the QPPs are co-phased within the wide spectral range (from microwaves to hard
X-rays). This could be evidence of the single source of the emission generating at
diﬀerent heights of the solar atmosphere and resulted by various mechanisms.
The results of the analysis are discussed in respect to a possible scenario ofenergy release during the flare and possibilities of their application for diagnosing
the acceleration processes at the initial phases of more powerful events.

37

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Physical Processes of Flux Emergence and Active Region
Formation
Abstract Author(s): Shin Toriumi
Institution(s): National Astronomical Observatory of Japan
Presentation: O2 013I
Abstract
This invited review is dedicated to the introduction of various physical processesof flux emergence and its resultant formation of active regions. The dynamogenerated magnetic flux rises through the convection zone and eventually appears at the surface as tiny pieces of magnetic elements of positive and negative
polarities. Through merging and cancellation, they gradually develop into larger
pores and sunspots, with exhibiting a wide variety of activity events including
bursts and jets. The representative of such events is solar flares, which is thecatastrophic release of magnetic energy stored in the active regions throughcomplex emergence of magnetic flux. In this talk, we will review important
physical processes of flux emergence in the interior and in the atmosphere, focusing especially on the recent progresses of both observational and theoretical
approaches.

38

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Realistic simulations of magnetic flux emergence from theconvection zone to the corona: Formation of solar active
regions and eruptions
Abstract Author(s): Feng Chen, Matthias Rempel, Yuhong Fan
Institution(s): High Altitude Observatory
Presentation: O2 014
Abstract
We present realistic simulations of emergence of magnetic flux generated in asolar convective dynamo from the convection zone to the corona. The magnetic
and velocity fields in a horizontal layer near the top boundary of the solar
convective dynamo simulation are used as a time-dependent bottom boundary todrive the radiative magnetohydrodynamic simulations spanning from the upper
convection zone to about 100 Mm in the corona. The main results are: 1) The
emerging flux bundles fragment into small-scale magnetic elements that further
rise to the photosphere and give rise to several bipolar sunspot pairs. The
large-scale flow pattern in the convection zone is not aﬀected in this process.
2) The mixed polarity magnetic field maintained by the small-scale dynamo in
the convection zone can provide suﬃcient energy to heat the Quiet Sun corona
to over one million K. As active regions are forming through flux emergencein the photosphere, the corona is further heated to three million K. 3) The
bipolar sunspot pairs formed in the photosphere preserve the asymmetries inthe emerging flux bundles and resemble the well-known asymmetries in observed
sunspot. 4) More than 100 flares occurs in about 50 hours, half of which areabove C class. The largest flare reaches M2.5 class and is associated the eruptionof a twisted flux rope.

39

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Two types of surge-like activities above sunspot lightbridges
Abstract Author(s): Hui Tian
Institution(s): Peking University
Presentation: O2 015
Abstract
Surge-like activities have been frequently reported from chromospheric observations of sunspot light bridges. Using NST and IRIS observations, we found
two types of surge-like activities at a sunspot light bridge. The type-I surges
appear above all locations at the light bridge at any time, likely driven by magnetoacoustic waves leaking upward from the photosphere. The type-II surges
are clearly caused by reconnection-driven jets which occasionally occur at somelocations of the light bridge. Evidences include the inverted Y-shape structuresat the footpoints of these jets in Halpha wing images and the IRIS bomb like line
profiles. The type-II surges are generally higher and brighter than the type-I
surges.

40

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Slender Ca II H Fibrils in the Low Solar Chromosphere
Abstract Author(s): Shahin Jafarzadeh, Sami Solanki, Rob Rutten, Sven
Wedemeyer, Ricardo Gafeira, Marco Stangalini
Institution(s): University of Oslo, Max Planck Institute for Solar System Research, Osservatorio Astronomico di Roma
Presentation: O2 016
Abstract
We present observations of dynamic, slender bright fibrils seen in high-quality
narrow-band Ca II H images from the SuFI instrument onboard the SUNRISE
balloon-borne solar observatory. We show that these slender Ca II H fibrils(SCFs) map magnetic fields in the low solar chromosphere derived from magnetostatic extrapolation of the photospheric field obtained with SUNRISE/IMaX
and SDO/HMI. Our analysis reveals the prevalence of magnetohydrodynamic(MHD) kink and sausage waves in the SCFs, propagating at high-frequencies(up to 30 mHz), with speeds on the order of 9-15 km/s. Characteristics ofthese waves diﬀer from those found for other fibrillar structures, which, however, were observed mainly in the upper solar chromosphere (from observations
with SST/CHROMIS). These MHD waves are found to be similar to those observed in the photospheric magnetic elements, but also penetrating into thelower solar chromosphere. The estimated energy flux (∼ 15 kW/m2 ) carried by
the observed waves in the SCFs is marginally enough to heat the chromosphere(and perhaps the corona). We have further explored temperature distributionsof the fibrillar structures from a coordinated observations between ALAM and
IRIS. The temperatures are compared with those determined in the fibrils as aresult of the MHD waves.

41

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Statistical study of small blue shifted events
Abstract Author(s): Kumi Hirose, Kiyoshi Ichimoto, Kenichi Otsuji, Takako
T. Ishii, Ayumi Asai
Institution(s): Kyoto University
Presentation: O2 017
Abstract
Solar Dynamics Doppler Imager (SDDI) which is equipped with the Solar Magnetic Activity Research Telescope (SMART) at Hida Observatory observed
many small blue shifted events. We present a statistical study of these events,
such as the occurrence frequency or the place where the events often observedin the solar surface. Routine observation using SDDI started from May 2016.
Using SDDI, we can get solar full disk images not only H-alpha center but
also the wing images from H-alpha -9.00A to H-alpha +9.00A, totally 73 wavelengths. According to the investigation of data totally 10 hours in August 2016,
the events occur about 10 times an hour. The sizes of them are about 10 to
20 arcsec, and that is equivalent to 10,000 km on the solar surface. The shift
amounts from H-alpha center are -1.25A to -2.00A, in other words, the line ofsight velocity is about 60 to 90 km/s. We discuss the result of the statistical
study about these blue shifted events using automatic detection algorithm. In
addition, we discuss the result of the comparison between SDDI data and SDO
data.

42

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Using the Solar Dynamics Observatory and Radiative
MHD Simulations to Study the Thermal Structure andEvolution of Solar Flares
Abstract Author(s): Mark Cheung
Institution(s): Lockheed Martin Solar and Astrophysics Laboratory
Presentation: O2 018K
Abstract
In part one of this presentation, we present a validated method to perform
diﬀerential emission measure (DEM) inversions on extreme ultraviolet imaging
observations of the solar corona taken by the Atmospheric Imaging Assembly
onboard NASAs Solar Dynamics Observatory. We begin with a description of
the method and proceed to discuss test cases used for validation. We thenpresent applications of the method to a number of science cases, including the(1) thermal structure of active regions and emerging flux regions, (2) magnetic
reconnection outflows and (3) chromospheric evaporation in solar flares. In
part two, we present results from a 3D radiative MHD model of a solar flareand compare synthetic remote sensing diagnostics with flare observations (e.g.
GOES X-ray light curve, temperature dependence of footprint evaporation flows
and x-ray spectra).

43

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Flux-Emergence Model for the Characterization of Solar
Active Regions
Abstract Author(s): Tetsuya Magara
Institution(s): Kyung Hee University
Presentation: O2 019I
Abstract
We present a model for characterizing solar active regions on the basis of theirevolutionary paths. To make a quantitative comparison of active regions having
diﬀerent morphological features, the model is used to derive physical propertiesof a subsurface magnetic field that characterize an active region formed throughflux emergence. The derivation is performed by inversion from an evolutionary
relation between two observables, emerged magnetic flux and injected magnetic
helicity, the former of which gives the scale information on active regions while
the latter represents their magnetic configurations.

44

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

ALMA observations of the solar chromosphere on thepolar limb
Abstract Author(s): Takaaki Yokoyama, Masumi Shimojo, Takenori J. Okamoto,Haruhisa Iijima
Institution(s): The University of Tokyo, National Astronomical Observatoryof Japan , Nagoya University
Presentation: O2 048
Abstract
We report preliminary results of the Atacama Large Millimeter/submillimeter
Array (ALMA) observations of the solar chromosphere on the southern polarlimb. The coordinated observations with IRIS and Hinode are also carried out.
ALMA has provided us unprecedented high spatial resolutions (approximately
1.5 arcsec) in the millimeter band at 100 GHz frequency with very high cadence(2 sec). The preliminary results are as follows: (1) A clear solar limb in the
millimeter band is located at approximately 5 arcsec above the photosphere.
(2) Many dynamic saw-tooth patterns are identified on the chromospheric edge.
They are co-located with the similar structure in the AIA 171 band and canbe interpreted as low-temperature high-density materials. (3) A blob-ejection
event is found. By comparing with the IRIS Mg slit jaw images, the trajectoryof the blob seems to be along the spicular patterns. The ejection is accompanied
by a brightening jet event at the footpoint area.

45

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Magnetic moment of thermal plasma and activities in thesolar atmosphere
Abstract Author(s): Kiyoto Shibasaki
Institution(s): Solar Physics Research Inc.
Presentation: P2 010
Abstract
Thermal plasma in the solar atmosphere is magnetized (diamagnetic) even underhighly collisional condition. According to the Classical Theory of Electromagnetism, magnetic moment is determined at each moment, hence the complete
gyration of charged particles around magnetic field is not needed. They do exist even in highly collisional thermal plasma. The Orbit Theory is not needed
to derive magnetic moment and drift motion. Magnetized fluid is subjected to
Kelvin force in non-uniform magnetic field. Generally, magnetic field strength
decreases upwards in the solar atmosphere, hence the Kelvin force is directed
upwards along the field. By adding the Kelvin force to the MHD equationof motion, we can expect temperature dependent plasma flows along the field
which are found by many observations. The temperature dependence of the flow
speed is explained by temperature dependence of magnetic moment. From theobserved parameters, we can infer physical parameters in the solar atmospheresuch as scale length of the magnetic field strength and the friction force acting
on the flowing plasma. Without the friction force, we can expect upward acceleration of plasma flow, which is the solar wind. In case of closed magnetic fieldlines, loop-top concentration of hot plasma is expected.

46

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Eﬀect of radiative loss on waves in chromosphere
Abstract Author(s): Yikang Wang, Takaaki Yokoyama
Institution(s): The University of Tokyo
Presentation: P2 011
Abstract
Radiation is one of the major tools for observing the sun. In the chromosphere,
it is even more important since it is a main source of energy loss, which has
a significant influence on chromosphere dynamics. While previous studies arelikely to ignore radiative loss due to its diﬃculty, we perform 1D radiative
MHD simulation and shown that the height of transition region and temperature
distribution in the chromosphere is aﬀected by radiative loss obviously. Our
research indicates that chromosphere heating and spicule launching could be
explained simultaneously by wave driving model, which also provides enoughenergy flux in coronal which may contribute to coronal heating.

47

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Comparative studies of the quiet sun under diﬀerent
conditions: in a coronal hole, under a magnetic canopy,
and pure quiet sun
Abstract Author(s): Daniela Adriana Lacatus, Alina Donea
Institution(s): Monash University
Presentation: P2 012
Abstract
A strong grasp of the quiet sun processes and their influence on the emitted
spectra is important in understanding the more dynamic active regions. We
use IRIS data to make a comparative study of the quiet sun under various
conditions: a) under the canopy fields of an active region b) in a coronal holeand c) in a pure quiet sun. We analyzed the chromospheric and transition regionlines profiles. The aim is to identify the network/internetwork diﬀerences on thequiet Sun while taking into account the evolution of the underlying magnetic
field and its influence. The Si IV and C II lines emission is barely visible above
the background in the cell interior while becoming relatively bright at the cellboundary. This clearly suggests that there is more heating in the network
lanes. Observational evidence was presented that the Mg II h&k lines exhibit asystematic broader line profile in the network region of a coronal hole, as a better
comprehension of the non-eruptive solar atmosphere is essential for current andfuture numerical simulations.

48

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Alfvén wave phase-mixing in flows: why over-dense solar
coronal open magnetic field structures are cool?
Abstract Author(s): David Tsiklauri
Institution(s): Queen Mary University of London
Presentation: P2 013
Abstract
The motivation for this study [1] is to include the eﬀect of plasma flow in Alfvénwave (AW) damping via phase mixing and to explore the observational implications. Our magnetohydrodynamic simulations and analytical calculations show
that, when a background flow is present, mathematical expressions for the AW
damping via phase mixing are modified by the following substitution: C A’ (x)→ C A’ (x) + V 0’ (x), where C A and V 0 are AW phase and the flow speeds,
and the prime denotes a derivative in the direction across the background magnetic field. Although the result is generic and is applicable to diﬀerent laboratory or astrophysical plasma systems, we apply our findings to addressing thequestion why over-dense solar coronal open magnetic field structures (OMFS)
are cooler than the background plasma. Observations show that the over-dense
OMFS (e.g. solar coronal polar plumes) are cooler than surrounding plasma
and that, in these structures, Doppler line-broadening is consistent with bulk
plasma motions, such as AW. If over-dense solar coronal OMFS are heated by
AW damping via phase-mixing, we show that, co-directional with AW, plasma
flow in them reduces the phase-mixing induced-heating, thus providing an explanation of why they appear cooler than the background.
[1] D. Tsiklauri, Astron. Astrophys. 586, A95 (2016)

49

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Solar Cycle Variation of Open Magnetic Flux Regions
Abstract Author(s): Chia-Hsien Lin, Guan-Han Huang , Lou-Chuang Lee
Institution(s): National Central University, Academia Sinica
Presentation: P2 014
Abstract
Coronal holes are the regions on the solar surface with magnetic field lines
extending far away from the Sun, allowing plasma to flow from the Sun into
interplanetary space, causing disturbance to the space weather. How coronalholes change over time can provide important information not only for space
weather and space climate, but also for the understanding of solar dynamo
and flux transportation. In this poster, we present our results on the spatialtemporal variation of coronal holes over 3.5 solar cycles.

50

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Stokes Profile Inversion code for the Photosphericspectral line
Abstract Author(s): Rahul Yadav, Shibu K. Mathew
Institution(s): Udaipur Solar Observatory
Presentation: P2 015
Abstract
Inversion codes are the most useful tools to infer the magnetic and thermodynamic properties of the solar atmosphere from the interpretation of Stokes
profiles. The basic idea of an inversion code is to minimize the diﬀerences between the observed and the synthetic Stokes profiles. A new Milne-Eddington(M-E) based inversion code (named as SPIN- Stokes Profile INversion) has beendeveloped at Udaipur Solar Observatory. The purpose of SPIN is to provide theresearchers a user-friendly tool for understanding and interpreting the spectropolarimetric observations. This code will be dedicated to analyze the pipeline
data of Multi-Application Solar Telescope (MAST) to extract the magnetic vector and velocity fields from the spectro-polarimetric observations. It solves thepolarized radiative transfer equation under M-E approximation and the inversion approach is based on the application of the modified Levenberg-Marquardt.
The code has been tested and validated with the other widely used inversion
codes like SIR and VFISV. We will present these results and describe the utilization of the SPIN code to invert the spectro-polarimetric data for a single
photospheric spectral line. We will also discuss the application of the SPIN to
invert the spectro-polarimetric data obtained from MAST and its comparison
with the HMI/SDO inverted data.

51

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Statistical analysis of formation of solar magnetic flux
tube with kilogauss magnetic field strength
Abstract Author(s): Shota Ninomiya, Kiyoshi Ichimoto
Institution(s): Kyoto University
Presentation: P2 016
Abstract
In the quiet region, there are ubiquitously flux tubes which have strong magnetic
field strength(1-2kG). These strong flux tubes are made by convective collapse.
There are many observations in time series but there are few statistical observations. In addition, time series observations are made by selecting a part of theflux tubes which convective collapse occurred. In this observation, we analyze
statistically the state of flux tube based on observations with the Solar Optical
Telescope (SOT) aboard Hinode.And we verify the formation scenario of flux
tube which have kilogauss magnetic field strength. As a result of analysis, there
are many flux tubes with physical quantities that agree with the conventional
formation model.

52

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Dark knots in a penumbral intrusion into a sunspot umbra
Abstract Author(s): Jingwen Zhang, Hui Tian , Haimin Wang
Institution(s): Peking University , New Jersey Institute of Technology
Presentation: P2 017
Abstract
High-resolution observations of the sunspot penumbra have revealed the existence of dark lanes in the center of penumbral filaments near umbral regions.
Previous studies speculated that these dark lanes are stagnant points abovemagneto-convection cells and that they are dark because of radiative loss. We
present very high-resolution TiO and Halpha images of a sunspot in NOAA
Active Region 12371 taken by the 1.6m New Solar Telescope at Big Bear Solar
Observatory on 2015 June 20. The observed region contains penumbral filaments intruding into the umbra and light bridges. The penumbral filaments
constantly intrude into the umbra and some of them develop into narrow lightbridges. The observation shows that the dark lane within a narrow light bridge
is not a continuous line but separated by many dark knots. These dark knots
appear to move inward along the light bridge, accompanied by brighter penumbral grains on both sides. Surge-like oscillations (light wall) can be identified
above the same light bridge in the Halpha core passband. In addition, the 1400
Angstrom and 2796 Angstrom slit-jaw images taken by the Interface Region
Imaging Spectrograph (IRIS) satellite reveal a few brightenings moving inward
on this light bridge, which appears to be related to the inward motion of dark
knots in the photosphere.

53

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Origin of three minute oscillations in a sunspot umbra
Abstract Author(s): Kyuhyoun Cho, Jongchul Chae
Institution(s): Seoul National University
Presentation: P2 018
Abstract
Three minute oscillations in sunspots are the observable aspect of slow mode
waves that can give us important clues to the sunspots structure and MHD
processes therein. We investigated the origin of the three minute oscillations
by observing the leading sunspot of AR 12663 on 2017 June 15 with the Fast
Imaging Solar Spectrograph. The Fe I 5434.5 angstrom line and the Ni I 5435.5
angstrom line were employed to measure velocity oscillations of the temperature
minimum region and the upper photosphere, respectively. We confirmed thatthe three minute oscillations on the sunspot umbra are upward propagatingwaves. More importantly, we estimated three minute oscillation power and thewave energy flux at the each layer, and examined their spatial, temporal distributions. Based on our results we discuss the possibility that magnetoconvection
inside sunspots may be the origin of three minute oscillations.

54

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Three-minute Sunspot Oscillations Driven by Magnetic
Reconnection in a Light Bridge
Abstract Author(s): Donguk Song, Jongchul Chae, Hannah Kwak, Ryouhei
Kano, Vasyl Yurchyshyn, Yong-Jae Moon, Eun-Kyung Lim, Jeongwoo Lee
Institution(s): National Astronomical Observatory of Japan, Seoul National
University, Big Bear Solar Observatory, Kyung Hee University, Korea Astronomy and Space Science Institute
Presentation: P2 019
Abstract
We report a new type of three-minute chromospheric oscillations above a sunspot
in association with a small-scale impulsive event in a light bridge. During ourobservations, we find a transient brightening in a LB. The brightening consistsof elementary bursts that are a manifestation of fast repetitive magnetic reconnections in a light bridge. Interestingly, the oscillations in the neighboring
region such as a sunspot umbra are impulsively excited when the intensity ofthe brightening in the light bridge reached at the peak. The initial period of
the oscillations is about 2.3 minutes and then gradually increased to 3.0 minutes. In addition, we find that the amplitude of the oscillations is twice larger
than before the brightening. Based on our results, we proposed a possibility
that magnetic reconnection occurring in a light bridge can unexpectedly lead to
excitation of oscillations in the nearby a sunspot umbra.

55

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Study of supersonic downflow at the transition region
above sunspots
Abstract Author(s): Tanmoy Samanta, Hui Tian, Sean McKillop
Institution(s): Peking University, Harvard-Smithsonian Center for Astrophysics
Presentation: P2 020
Abstract
Downflows at supersonic speed have been observed in the transition region above
sunspots for more than two decades. These downflows are often seen in diﬀerent
transition region spectral lines above sunspots, although, it is still poorly understood why these strong downflows at supersonic speed exists within sunspots.
We try to emphasize the important properties these downflows by performing astatistical analysis over a large sample which was missing earlier. The Interface
Region Imaging Spectrograph (IRIS) has provided a wealth of high- spatial andspectral resolution observational data of sunspots in the past few years. We haveidentified sixty datasets obtained with IRIS raster scans. Using an automatedcode we identified the locations of strong downflows within these sunspots. We
found that around eighty percent of the sunspots show supersonic downflows in
the Si IV 1403 Å line. Furthermore, a detailed spectral analysis was performedby selecting a small spectral window containing the O IV 1399 Å, O IV 1401 Å
and Si IV 1403 Å transition region lines. Six Gaussian functions were simultaneously fitted to these three spectral lines and their satellite lines (due to strong
down flows). We calculated the intensity, Doppler velocity and line width forthese lines. We also computed the density using the O IV doublet line ratio forboth the static and downflow components. We also discuss the source of thesesupersonic downflows.

56

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Foot point Brightening at near pore boundary
Abstract Author(s): Juhyeong Kang, Jongchul Chae
Institution(s): Seoul National University
Presentation: P2 021
Abstract
We investigate fine scale transient brightening event at the pore boundary. We
observed the pore on June 4, 2014, from the Fast Imaging Solar Spectrograph(FISS) of the 1.6 m Goode Solar Telescope (GST), the Atmospheric Imaging
Assembly (AIA) aboard the Solar Dynamics Observatory (SDO), and Helioseismic and Magnetic Imager (HMI) aboard SDO. The event occurs at foot point of
the loop with a conjugate brightening at the other foot point outside the FISS
field-of-view. These foot point brightening events appear in all AIA extreme
ultraviolet bands, also in the two FISS lines, H and Ca II 8542 Å, and last fora minute. The Brightening near the pore boundary exhibit a redshift of 4.3 km
s-1 in the H, and about 2.3 km s-1 in Ca II line. Diﬀerential emission measure
derived from the AIA passbands and cloud model fitting of the two FISS lines
show the temperature increase between 10,000 and 20 MK at the main event.
After the brightening, the upward mass motion is found in EUV bands of AIA.
This brightening is possibly related the foot point brightening caused by themagnetic reconnection.

57

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Flows along the Super-Penumbral Fibrils in Sunspots
Abstract Author(s): Debi Prasad Choudhary, Christian Beck
Institution(s): San Fernando Observatory
Presentation: P2 022
Abstract
Sunspots are main ingredient of solar cycle and site of major eruptive events.
Understanding the structure of these objects is an important aspect studying ournearest star. We have observed several sunspots using the Spectropolarimeterin near-Infrared and Optical wavelength ranges at the Dunn Solar Telescopeduring 29 July to 4 August 2013. The data consists of full Stokes profiles in
the Ca II 854.2 nm and Fe I 1.56 micron lines. The inversion of these Stokes
spectra provides the magnetic, thermal and velocity structure at photosphericand chromospheric heights of sunspots. In this lecture, we present the resultson the 3D thermal structure in the superpenumbral canopy of a round sunspot,
derived by a novel approach for the inversion of Ca II IR spectra. Tracing
individual fibrils in the super-penumbral canopy, we find that about half ofthem form only short loops of a a few Mm length that return to the photospherein the close surroundings of the sunspot instead of connecting to more remotemagnetic network at the outer end of the moat flow. We also find indications forstanding shocks at the inner foot points of the flow channels that are compatible
with a supersonic siphon flow scenario scientific matters.

58

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Emergence of running penumbral waves in the sunspots
Abstract Author(s): Priya TG
Institution(s): NAOC
Presentation: P2 023
Abstract
We present the results from high resolution imaging observations of runningpenumbral waves (RPWs) in active region NOAA 12127 with three sunspots.
The spectra of TiO, H, and 304 Å for various atmospheric heights from thephotosphere to lower corona are used to investigate the emergence of RPWs in
the chromosphere. Analysis show that at the formation height of H 0.6 Å in the
inner umbra, the power of 4.2-8.0 min oscillations accounts for ∼5% and ∼3%of 2.64.2 min and 1.92.6 min oscillations, respectively. We found consistency
in the average power of these oscillations from H -0.6 Å upto H line center,indicating that the signal of 5-min oscillations is very weak to be easily detectedin the inner umbra even if they exists. We used a phase-speed filter to extract
the wave signals from the temporal sequences of H images and found that thewaves with periods of 3 min and ∼4.2 min simultaneously emerge in the umbral
center, and the intensity of the latter is ∼2% of the former (comparable to theabove 3% or 5% proportion). Interestingly, we found that the 3 min waves
become evanescent and ∼4.2 min gets enhanced while approaching the umbral
boundaries, suggesting that RPWs might emerge in the center of chromosphericumbra. Similar results are obtained from the analysis of single sunspot of NOAAAR 12132, showing the consistency.

59

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Velocity oscillations in the chromosphere and transition
region above plage region
Abstract Author(s): Hannah Kwak
Institution(s): Seoul National University
Presentation: P2 024
Abstract
We closely investigate velocity oscillations in the active region plage by using
the high-spatial, high-spectral and high-temporal resolution spectral data acquired by the Interface Region Imaging Spectrograph. From the Mn I 2801.907
Å (lower chromosphere), Mg II k (chromosphere), C II (lower transition region)and Si IV (middle transition region) lines, we measure the line of sight Doppler
velocity at diﬀerent atmospheric layers, and present results of wavelet analysis of plage region with a range of periods from 2 to 8 minutes. In addition,
we present correlations of the oscillations from the lower chromosphere to the
middle transition region. Finally, we try to understand the regional dependenceof the oscillation properties on physical properties such as temperature andmagnetic field inclination.

60

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Analysis of Ellerman Bomb Spectra Observed by FISS
Abstract Author(s): Minju Seo, Jongchul Chae, Jeongwoo Lee
Institution(s): Seoul National University
Presentation: P2 025
Abstract
Ellerman bombs (EBs) are small transient events occurring near active regionsthat appear bright in the far wings of the Balmer lines and are believed tobe due to magnetic reconnection. To estimate the heating function for EBs,
we analyze the EB spectra observed by the Fast Imaging Solar Spectrograph(FISS) installed on the 1.6m Goode Solar Telescope (GST) in Big Bear Solar
Observatory (BBSO), which provide H-alpha and Ca II 8542 Å line profiles withhigh-spectral resolution. We have mainly compared the FISS spectra of EBs
with synthetic profiles computed using RH non-LTE radiative transfer code withthe 1D atmospheric models. To model the heating, we introduce a temperatureenhancement in Gaussian form that vary in magnitude and height, as consideredadequate for EBs. In this way, we could reproduce each of the observed H-alphaand Ca II line profiles separately with diﬀerent atmospheric models, but not witha single atmospheric model. It is often the case that the best-fit model for theobserved H-alpha lines has much higher temperature enhancement than that for
Ca II lines. We discuss possible causes for this temperature mismatch such as
non-thermal heating which is not included in our model.

61

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Observation of Fine Scale Dynamics in the Solar
Chromosphere with a Dual Camera Imaging System
Abstract Author(s): Satomi Tokuda, Aki Machida, Sanetaka Okada, Satoru
Ueno, Kiyoshi Ichimoto
Institution(s): Kyoto University
Presentation: P2 026
Abstract
Using a newly developed narrowband universal tunable filter (UTF-32) equippedwith a polarizing beam splitter at the exit and the following two cameras, we
can take solar images in Ha(6563Å) +/-0.5Å simultaneously. It allows us to obtain accurate Dopplergrams with much suppressed seeing noise since two images
in Ha+0.5Å and Ha-0.5Å suﬀer from exactly same distortion or blurring due tothe seeing. Thus, by applying an image reconstruction technic on the diﬀerence
images of Ha+/-0.5Å , it is possible to deduce a high resolution Dopplergram.
We observed an active region (NOAA 12665) near the west limb on July 15,2017 with the UTF dual camera system installed on the Domeless Solar Telescope (DST) of the Hida Observatory of Kyoto University. By applying the
speckle masking image reconstruction to the observed dataset, we obtained atime series ( 80min duration and 10sec cadence) of Ha images and Dopplergramswith nearly diﬀraction limited spatial resolution for the aperture size of 60cm
( 0.25arcsec). We expect that this kind of observation with high resolution willallow us to investigate the time evolution of plasma flows along chromosphericfibrils, twisting motions of small jets, oscillations in filaments or prominences,and eventually to understand the origin of the fine scale dynamics in the solar
chromosphere. We will present the details of our observing system and discuss
the analysis results of the observation.

62

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

High Resolution Observations of Spicules inUpper-Photospheric Lines
Abstract Author(s): Yoshinori Suematsu
Institution(s): National Astronomical Observatory of Japan
Presentation: P2 027
Abstract
The formation mechanism of the chromospheric spicules remains unresolved, although there is no doubt that they are rooted at photospheric magnetic elements
most of which are seemingly unipolar. It is likely that a key mechanism for theirformation is a strong slow shock formation in the chromosphere, irrespective of
its original energy source, such as a p-mode acoustic wave leakage into the chromosphere, MHD wave propagation including torsional Alfven waves launched in
the photosphere, magnetic reconnection happening in the lower chromosphere,
etc. The formation mechanism should explain not only their tall height but also
their narrow width; large aspect ratio of length to width, their multi-thread
structure typically double-thread. It is likely that the some spicules are rooted
in the upper photosphere since their roots show up as tiny jets in Dopplergrams in Na I D and Mg I b lines close to the limb and even on the limb, as
observed in Hinode/SOT Narrow-band Filtergraphic Imager. This fact implies
that the spicules start below the chromosphere and pressure waves need to begenerated in the sub-photosphere: One of possible mechanisms for the wave
generation might be a magnetic pumping suggested by Parker (1974). I present
observational results of spicule-like jets in the upper-photospheric lines.

63

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Wave Propagation on Spicules Observed by
Chromospheric Lyman-Alpha Spectro-Polarimeter(CLASP)
Abstract Author(s): Masaki Yoshida, Y. Suematsu, R. Ishikawa, R. Kano,
N. Narukage, T. Bando, A. Winebarger, K. Kobayashi, J. Trujillo Bueno,
F. AuchereInstitution(s): The Graduate University for Advanced Studies , National Astronomical Observatory of Japan, NASA Marshall Space Flight Center,
Instituto de Astrofisica de Canarias, Institut d’astrophysique spatiale
Presentation: P2 028
Abstract
The MHD wave propagations on spicules are detected by Hinode and IRIS. They
are considered to be a sign of mechanical energy transport for coronal heating
and solar wind acceleration. To study the wave propagation on the spicule, we
analyzed the Ly-alpha line spectro-polarimetric data of limb spicule from the
CLASP sounding rocket experiment. The Ly-alpha line is well suited for the
study of wave propagation of spicule because it shows up taller and longer-lived
spicules than other chromospheric lines due to its very large opacity. Therefore,
we derived the velocity field along the height of the spicule. For the study ofline-of-sight doppler motion, to avoid the influence of geo-coronal absorption at
the line center, we use a method called bisector analysis at the Ly-alpha line
wing. As a result, we succeeded in detection of the wave propagation along
the spicule. The oscillation have a short period ( 30 seconds) and a long period( 240 seconds: observed only in half period). The velocity amplitudes are ∼7 km
s−1 in short period and ∼20 km s−1 in long period. The propagation velocity is∼500 km s−1 . If this oscillation assumed to be MHD kink wave, a magnetic fieldof spicule could be estimated about 2080 G when typical densities of spicules
are assumed. Upward pointing flux could be estimated to be 3×106 -6×107 erg
cm−2 s−1 from the long period velocity amplitude and the magnetic field. The
pointing flux is large enough to heat the corona in the quiet Sun.

64

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Driving process for highly impulsive plasma outflows
Abstract Author(s): Yamini K. Rao, A. K. Srivastava, J. G. Doyle, Bhola
N. Dwivedi
Institution(s): Indian Institute of Technology , Armagh Observatory
Presentation: P2 029
Abstract
A study on an impulsive plasma outflow was conducted in the quiet-Sun using
multi-wavelength datasets from Atmospheric Imaging Assembly (AIA) onboard
Solar Dynamics Observatory (SDO) on 2011 March 30. This small-scale impulsive plasma outflow was found to be of the size ∼8 arcsec with a lifetimeof ∼8 minutes. The simultaneous emissions from multiple SDO/AIA channels
covering wide temperature range, indicated its impulsive behavior. An unusualhigh terminal speed of 1250 km s−1 was observed with which the outflow rose to
the upper solar atmosphere. We also studied the temperature distribution of its
plasma by an automated DEM technique using AIA wavebands sensitive to thetransition region and coronal temperatures. The evolution of photospheric magnetic field was investigated using SDO/HMI temporal image data which showed
the signature of negative flux emergence in the vicinity of a positive flux region.
The negative flux was found to be oscillating with the period of 442s. The flux
cancellation is evident from the topological behavior of magnetic polarities at
the footpoint of the brightening. The oscillations with almost same period 416
s(∼7 min) was observed in 1600 Å wavelength of SDO/AIA and flux from thenegative polarity at the base of the outflow region before, during, and even after
the outflow. This indicated the generation of magnetoacoustic waves/shocks inthe small- scale current sheet which supplied the energy required to drive theimpulsive plasma outflow.

65

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

H-alpha surges at the emerging flux region observed
before the pore formation (NOAA 12660)
Abstract Author(s): Takako T. Ishii, K. Otsuji, T. Anan, K. Ichimoto
Institution(s): Kyoto University
Presentation: P2 030
Abstract
We observed point like jets and surges at the emerging flux region before/during
pore formation (NOAA 12660) on 2017-May-22(JST) with SMART/SDDI at
Hida Observatory, Kyoto University. SMART/SDDI (Solar Dynamics Doppler
Imager) takes full-disk solar images with a field of view of 2520 arcsec2 at multiple wavelengths around the H-alpha line (from 6561.9 Å to 6563.7 Å, withresolution of 0.25 Å). Comparing H-alpha surge activities and magnetic fieldevolution using SDO/HMI data, we found following results. (1) At the beginning of observation (21:45UT), this region was covered by weak negative
polarity. (2) Point like jets(surges) occurred continuously from 22:00 UT to
01:00UT. (3) Positive polarity flux appeared around 22:30UT. (4) AFS (Archfilament system) in H-alpha was seen around 03:00 UT, and pore with negative
polarity was formed. (5) Around 05:00 UT, pore with positive polarity wasformed. (6a) After 01:00UT, long surges occurred. (6b) After the formationof AFS, large surges occurred. This result is the first observational result withmagnetic field data confirmed Kurokawa (1988 Vistas in Astronomy), the firstmanifestation of the emerging flux region in the solar surface is a surge activity.

66

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Large-amplitude prominence oscillations: observations
and numerical simulations
Abstract Author(s): Qingmin Zhang
Institution(s): Purple Mountain Observatory
Presentation: P2 031
Abstract
We report our studies on observations and numerical simulations of large-amplitude
prominence/filament oscillations. Using the multi-wavelength observations from
Hinode, SDO, and GONG, we studied the longitudinal oscillations of an AR
prominence and an intermediate filament, simultaneous longitudinal and horizontal oscillations of a quiescent prominence, and vertical oscillation of a polar
coronal cavity. Numerical simulations are performed to investigated the triggering mechanism, restoring force, and damping mechanism of oscillations. The
longitudinal oscillations are mainly triggered by microflares in the filament channels. However, a new mechanism of triggering mechanism is found, i.e., jet-likeflows from a remote flare. The restoring force of longitudinal oscillations ismainly the projected gravity of filament along the dip. However, the magnetic
pressure gradient may play an important role in the restoring force for the magnetic flux rope hosting a prominence. The damping mechanism of longitudinaloscillations is mainly radiative loss. However, downward mass drainage fromone of the prominence legs may accelerate the damping of amplitude. For vertical oscillations, they can be triggered by large-scale EUV waves from a remotesite of solar eruption.

67

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

The Role of a Flux Rope Ejection in a Three-dimensional
Magnetohydrodynamic Simulation of a Solar Flare
Abstract Author(s): Keisuke Nishida, Naoto Nishizuka, Kazunari Shibata
Institution(s): Kyoto University, National Institute of Information and Communications Technology
Presentation: P2 032
Abstract
We investigated the dynamic evolution of a three-dimensional (3D) flux rope
eruption and magnetic reconnection process in a solar flare, by simply extending
two-dimensional (2D) resistive magnetohydrodynamic simulation model of solar
flares with low beta plasma to 3D model. We succeeded in reproducing a current
sheet and bi-directional reconnection outflows just below the flux rope during
the eruption in our 3D simulations. We found that there is a positive feedback
between the ejection speed of a flux rope and the reconnection rate both in the
2D and 3D simulations, and we conclude that the plasmoid-induced reconnection
model can be applied to 3D. We also found that small scale plasmoids areformed inside a current sheet and make it turbulent. These small scale plasmoid
ejections have a role in locally increasing the reconnection rate intermittently
as observed in solar flares, coupled with a global eruption of a flux rope.

68

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Three-dimensional MHD simulation of solar prominence
oscillations in a magnetic flux rope
Abstract Author(s): Yuhao Zhou, Chun Xia, Rony Keppens, Pengfei Chen
Institution(s): Nanjing University, University of Leuven
Presentation: P2 033
Abstract
Solar prominences are always subject to all kinds of perturbations during their
lifetime, which lead to the frequently observed prominence oscillations. The
study of prominence oscillations provides an alternative way for investigating
their internal structure as well as their interplay with the solar corona. A number of theoretical models as well as one- or two-dimensional simulation works
have been performed to explain the observed periods of these oscillations. In
this work, we present a three-dimensional magnetohydrodynamic simulation ofprominence oscillations in an elongated magnetic flux rope, with the help of thenumerical code MPI-AMRVAC. It is found that, while the oscillation periods
predicted by analytical solutions are roughly consistent with our numerical results, the latter does show some new features that are missing in the simplified
analysis. These results would be helpful to improve prominence seismology.

69

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Determination of the wave property in the quiescentprominence from the phase diﬀerence
Abstract Author(s): Aki Machida, Kiyoshi Ichimoto, Sanetaka Okada, Satomi
Tokuda, Ayumi Asai, Satoru Ueno, Kazunari Shibata
Institution(s): Kyoto University
Presentation: P2 034
Abstract
The mechanism of coronal heating has not yet been fully solved. One of the hypotheses is dissipation of waves. To understand the wave dynamics, prominences
are good target, since they are denser, and therefore, variations of physical parameters are more detectable than the surrounding corona. Thus, it is expectedthat investigating wave dynamics in prominences give some suggestions to thecoronal heating problem. Not only from observations of Doppler velocity but
also from those of temperature simultaneously, we can understand the wave dynamics in more detail. If the temperature has the periodicity, we can conclude
whether the wave is compressive or not. From the phase diﬀerence between
the temperature and the Doppler velocity variations, we can determine that thewave is a propagating wave or a standing wave. Furthermore, from the time variation of the temperature, we can capture the process in which the wave damps
and is converted into the heat energy. On 16 October 2016, we observed theprominence with the Domeless Solar Telescope and the horizontal spectrographat the Hida Observatory, Kyoto University. From the simultaneous observation of three spectra, Ha(6563A), Hbeta(4861A), and Ca(8542A), we detected
the quasi-periodic time variations of the temperature and the Doppler velocity.
From the phase diﬀerence of 180 degree, it is concluded that we captured the
propagating magneto-acoustic wave.

70

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Temperature diagnosis of Solar prominences with asimultaneous observation of H-alpha, H-beta and Call
8542Å lines
Abstract Author(s): Sanetaka Okada, Aki Machida, Satomi Tokuda, Kiyoshi
Ichimoto, Satoru, Ueno, Ayumi Asai, Kazunari Shibata
Institution(s): Kyoto University
Presentation: P2 035
Abstract
We observed a solar prominence on the east limb with the Domeless Solar Telescope at Hida observatory on October 16 2016. We scanned the prominence by
the slit of the spectrograph and obtained the spectra of Ha. Hbeta, Ca 8542 ateach point of the prominence. By fitting the profiles of obtained spectra using
a simple 1D slab model, we determined the doppler width of the spectra ateach point of the prominence and obtained the distribution of temperature(T)and turbulent velocity(ξ). In the fitting we considered the fine structure of Ha
and Hbeta lines and found that the derived temperature diﬀers by about 1000K
from the results when the fine structure is ignored. We also examined the optimized way for constraining the fitting parameters and finally fixed the ratios
of opacity and source function of H-alpha and H-beta in order to better determine the optical thickness and the Doppler width of the hydrogen lines with ahigher confidence. From the fitting of three lines, at the top of the prominence
we found high temperature region (T∼15000K) with high turbulent velocity(ξ ∼10km/s). This suggests that turbulence is related to the heating of theprominence.

71

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Statistical Study of the Magnetic Field in Solar Filaments
Abstract Author(s): Yoichiro Hanaoka, T. Sakurai, IRMag Group
Institution(s): National Astronomical Observatory of Japan
Presentation: P2 036
Abstract
We carried out a statistical study of the magnetic field orientation in solar filaments based on our daily full-Sun, full-Stokes spectropolarimetric observations
with the He I 10830 line. The analysis of more than 400 filaments revealed thatthe average direction of the magnetic field in filaments generally deviates fromtheir axis by 10-30 degrees, and the direction of the deviation strongly depends
on the hemisphere where the filaments appear. This hemispheric pattern is
consistent with the well-known chirality pattern of the fine structure seen infilaments, and for some of the filaments we can confirm that the magnetic field
direction is parallel to that of the fine structure in the filaments. Filaments
sometimes erupt as a part of CMEs, and therefore, magnetic field informationof filaments taken with the full-Sun observation is important from the viewpointof the space weather.

72

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

H-alpha absorption profile of erupting filament
Abstract Author(s): Huang Yuwei, Kiyoshi Ichimoto
Institution(s): Kyoto University
Presentation: P2 037
Abstract
H-alpha is the most important chromospheric line in solar observation, especiallyin prominence and filament observation. However, as pointed out by Hyder andLites (1970), H-alpha Doppler brightening and Lyman-alpha dimming eﬀects
due to apparent Doppler shifts will strongly modify the H-alpha emission profile of prominence, and these Doppler velocity dependency was demonstrated
quantitatively using non-LTE techniques by Heinzel and Rompolt (1987). In
contrast to Heinzel and Rompolt (1987), whose hydrogen energy levels belonging to the same principal quantum number n are degenerate, we developed a
non-LTE radiative transfer code which includes the consideration of forbidden
transition between levels with diﬀerent angular momentum J, to investigate thebehavior of the absorption profile of erupting filament. Furthermore, we compare our quantitative analysis with the filament eruption data obtained by the
Solar Dynamic Doppler Imager (SDDI), a new instrument developed in Hidaobservatory to monitor full solar disk in H-alpha with a wavelength range of ±9Å, to investigate the dynamic motion of erupting filaments.

73

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Observation of the Streaming-Kink Instability in the Solar
Prominence
Abstract Author(s): Heesu Yang
Institution(s): Korea Astronomy and Space Science Institute
Presentation: P2 038
Abstract
Many solar prominences end their lives through eruptions or abrupt disappearances that are associated with the thermal or dynamical instabilities. Suchinstabilities are very important at the Sun because they may have a big responsiblility for energy transport and conversion. We present a clear observation of
the Streaming-Kink Instability (SKI) taking place in a solar prominence on thelimb observation using the Hα Lyot filter installed at the New Vacuum Solar
Telescope, Fuxian Solar Observatory in Yunnan, China. Beside the prominence,
plasma floated up from the chromosphere and streamed parallel to the limb. The
plasma stream is accelerated to the velocity of about 20 - 60 km s−1 and thenundulated. We found that the 2 and 5-size vortices formed in the stream, andthey floated along the stream and then broken up. After breaking of the 5-size
vortex, plasma appeared to eject from the stream in the AIA images. We attribute the phenomenon to the SKI triggered by the velocity shear between thestream guided by the magnetic field and the surrounding media. The plasmaejection may indicate a considerable transport of the prominence material into
the upper layer by magnetic reconnection at the vortices.

74

APSPM 2017
Session 2: MHD processes in photosphere, chromosphere and corona

Doppler Characteristics and Dynamics Processes of theMoreton Wave on 2014 March 29
Abstract Author(s): Denis P. Cabezas, Ayumi Asai, Satoru UeNo, Kiyoshi
Ichimoto, Kazunari Shibata
Institution(s): Kyoto University
Presentation: P2 039
Abstract
Shock waves are fundamental physical processes in solar and stellar plasmas.
Their properties and eﬀects have widely been discussed in the framework ofmagneto-hydrodynamics (MHD) theory. In the Suns chromosphere a largescale wavelike propagating disturbance, known as Moreton wave, occasionallyhappens in association with strong flares and coronal mass ejections (CMEs). In
this work we present a study of the Moreton wave that accompanied an X-classflare on 2014 March 29. This event was successfully detected in multiwavelength
imaging in Ha line by the Flare Monitoring Telescope (FMT) installed in Peru.
We made use of FMT wing (Ha-0.8A and Ha+0.8A) observations to investigate
the Doppler features of the Moreton wave, as well as its dynamic and the shock
characteristics. The Doppler analysis clearly shows a downward motion of thechromospheric plasma, this might indicate plasma compression due to the wave
propagation in the corona. In addition, the coronal plasma responses are also
examined, since fast-mode wave propagating in the corona was associated withthe event under study. We use Hinode XRT data to derive the temperature andthe plasma condition as the wave propagates in the corona. We complement
our investigation with the SDO/AIA data, from which the diﬀerential emission
measure (DEM) has been extracted.

75

APSPM 2017

Session 3
Flare, ejection and space weather

76

APSPM 2017
Session 3: Flare, ejection and space weather

Modelling of superactive delta sunspots in the Sun
Abstract Author(s): Piyali Chatterjee
Institution(s): Indian Institute of Astrophysics
Presentation: O3 022I
Abstract
Active regions (AR) appearing on the surface of the Sun are classified into alpha, beta, gamma, and delta by the rules of the Mount Wilson Observatory,
California on the basis of their topological complexity. Amongst these, the deltasunspots are known to be super-active and produce the most X-ray flares. Here,
we present results from a simulation of the Sun by mimicking the upper layers
and the corona, but starting at a more primitive stage than any earlier treatment. We find that this initial state consisting of only a thin sub-photosphericmagnetic sheet breaks into multiple flux-tubes which evolve into a collidingmerging system of spots of opposite polarity upon surface emergence, similar to
those often seen on the Sun. The simulation goes on to produce many exotic
delta-sunspot associated phenomena: repeated flaring in the range of typical solar flare energy release and ejective helical flux ropes with embedded cool-dense
plasma filaments resembling solar coronal mass ejections. Further, we demonstrate that these simulated solar flares can be predicted in time and height insolar atmosphere using the method of weighted magnetic gradient which uses
the distance between barycenters of two opposite polarities in the active region
as a precurser for solar flares.

77

APSPM 2017
Session 3: Flare, ejection and space weather

Spectral features of an X-shaped flare as implications forenergy release and dynamics in the flare atmosphere
Abstract Author(s): Mingde Ding, Ying Li, Jie Hong
Institution(s): Nanjing University, Purple Mountain Observatory
Presentation: O3 023
Abstract
We present the spectral observations of an X-shaped flare on 2014 November
9 that was observed by IRIS. The flare shows some peculiar spectral features
including broadened Si V line wings at the X-point and a wholly red-shifted
Si V line at the flare ribbon, which are possible signatures of direct energy
release (magnetic reconnection) in a lower site and the dynamic response of thechromosphere to an electron beam heating. We make some preliminary radiativehydrodynamic simulations to check the origin of the spectral features.

78

APSPM 2017
Session 3: Flare, ejection and space weather

High Resolution Flare Observations with the 1.6 m NST
at BBSO
Abstract Author(s): Haimin Wang, Hossein Safari, Nasibe Alipour, Michael
S. Wheatland
Institution(s): New Jersey Institute of Technology, University of Zanjan, The
University of Sydney
Presentation: O3 024K
Abstract
This talk presents some exciting new results of 1.6m Goode Solar Telescope(GST, formally named as NST) at Big Bear Solar Observatory (BBSO). I willreport: (1) Flare ribbons and post-flare loops are observed in the scale of around
100 to 200 km. (2) the sudden flare-induced rotation of a sunspot. It is clearlyobserved that the rotation is non-uniform over the sunspot: as the flare ribbon
sweeps across, its diﬀerent portions accelerate at diﬀerent times corresponding
to peaks of flare hard X-ray emission. The rotation may be driven by the surface
Lorentz-force change due to the back reaction of coronal magnetic restructuring and is accompanied by a downward Poynting flux. (3) We found the clear
evidence that electron streaming down during a flare can induce extra transienttransverse magnetic field that cause apparent rotation only at the propagating
ribbon front. Sometimes they are associated with so called negative flares in HeI
10830 and D3 lines. (4) We found evidence that episodes of precursor brightenings are initiated at a small-scale magnetic channel (a form of opposite polarity
fluxes) with multiple polarity inversions and enhanced magnetic fluxes and currents, lying near the footpoints of sheared magnetic loops. The low-atmosphericorigin of these precursor emissions is corroborated by microwave spectra. (5)Twisted magnetic flux ropes are observed and analyzed in comparison with
NLFFF extrapolation.

79

APSPM 2017
Session 3: Flare, ejection and space weather

Blue asymmetry of the chromospheric Mg II lines in asolar flare
Abstract Author(s): Akiko Tei, Takahito Sakaue, Takenori J. Okamoto, Tomoko
Kawate, Satoru UeNo, Ayumi Asai, Kiyoshi Ichimoto, Kazunari Shibata
Institution(s): Kyoto University, National Astronomical Observatory of Japan, Japan Aerospace Exploration Agency
Presentation: O3 025
Abstract
In solar flares, dynamic phenomena occur in the chromosphere, while the details of the dynamics and the mechanism of energy injection are still unknown.
Chromospheric observations of flares lead us to a new understanding of heating
mechanisms of the chromosphere, energy transports, and energy release processes in the corona. We performed coordinated observations of AR 12205,
which produced a C-class flare on 2014 November 11, with IRIS and DST at
Hida Observatory. Using spectral data by IRIS and DST, we investigated thetemporal and spatial evolution of the flare in the chromosphere. We detected aflare ribbon apparently moving 9 along the IRIS slit with a propagation speedof about 31 km/s during the impulsive phase of the flare. The flare kernels
showed intensity enhancement in the blue wing (blue asymmetry) prior to a
drastic change of the intensity in the red wing (red asymmetry) only in the Mg
II h line. At the locations that the flare ribbon passed over, the blueshifts witha speed of up to 17 km/s lasted for about 40 s and were followed by the strong
redshifts with a speed of 58 km/s for 50-100 s. We suggest that the observed
phenomenon is explained by an upflow of the chromospheric-temperature (cool)
plasma lifted up by the evaporated (hot) plasma owing to the penetration of
non-thermal electrons into the deep chromosphere.

80

APSPM 2017
Session 3: Flare, ejection and space weather

Analysis of Hard X-ray and Microwave Observations with
Fokker-Planck Model in Solar Flares
Abstract Author(s): Yu-Lun Liou, Ya-Hui Yang
Institution(s): National Central University
Presentation: O3 026
Abstract
The electrons accelerated to several MeV during flare impulsive phase are believed to be responsible for the non-thermal emissions in hard X-ray (HXR) andmicrowave observations. In order to understand the behaviors of these nonthermal electrons, we analyze a M2.3 flare on 2014 September 23 by combining
the RHESSI and Nobeyama measurements. The microwave peak is observed to
be 20s later than HXR peak, which is diﬀerent from the typical delay time ofseveral seconds presented in most previous events. The HXR sources are appeared as double chromospheric footpoints in RHESSI CLEAN maps with thesoft-hard-harder (SHH) spectral profile, while the microwave emission is shownas loop-top source in Nobeyama 17 GHz images with the SHH pattern. In
addition, microwave spectrums are harder compared with the HXR spectrum.
By solving the spatially homogeneous Fokker-Planck equation with diﬀerent
energy, we further calculate the spectral indices of precipitating and trapping
non-thermal electrons for HXR and microwave emission respectively to explain
the trapped eﬀect on the high-energy electron spectrum.

81

APSPM 2017
Session 3: Flare, ejection and space weather

Models of diﬀusive and nondiﬀusive transport of solar
energetic particles
Abstract Author(s): Yuri Litvinenko
Institution(s): University of Waikato
Presentation: O3 027
Abstract
When energetic particles propagate in interplanetary space following powerfulsolar flares, the particles interact with a turbulent interplanetary magnetic field.
As a result, the transport of the solar energetic particles is diﬀusive. A diﬀusion
equation for the particle density is known to approximate the Fokker-Planck
equation when the particle pitch angle distribution is weakly anisotropic. The
evolution of strongly anisotropic particle distributions on time scales that areshorter than or comparable with a characteristic scattering time leads to nondiffusive behavior. The nondiﬀusive transport of the solar energetic particles has
been a subject of much recent research interest. I will review possible refinements of the basic diﬀusion model and present a detailed side-by-side comparisonof an evolving particle density profile, predicted by the telegraph and hyperdiffusion models in the context of a physically meaningful initial-value problem. I
will also compare the predictions with the solution based on the Fokker-Planck
equation and discuss the applicability of the approximations to the transport ofstrongly anisotropic particle distributions in interplanetary space.

82

APSPM 2017
Session 3: Flare, ejection and space weather

Particle-In-Cell, fully kinetic scale modeling of solar radio
burstsAbstract Author(s): David Tsiklauri
Institution(s): Queen Mary University of London
Presentation: O3 028
Abstract
Basic physics of the radio emission mechanisms of solar type III bursts will bebriefly reviewed. A case will be made for alternatives to plasma emission, suchas non-gyrotropic electron beam [1-3]. Further self-consistent particle-in-cellsimulations of fundamental and harmonic radio plasma emission mechanisms
will be presented [4]. Also, particle-in-cell simulations of the relaxation of electron beams in inhomogeneous solar wind plasmas [5] will presented, alleviating
the problem of the beams travelling large interplanetary distances without experiencing quasilinear relaxation.
[1] D. Tsiklauri, Phys. Plasmas 18, 052903 (2011)[2] H. Schmitz, D. Tsiklauri, Phys. Plasmas, 20, 062903 (2013)[3] M. Skender, D. Tsiklauri, Phys. Plasmas 21, 042904 (2014)[4] J.O. Thurgood, D. Tsiklauri, Astron. Astrophys. 584, A83 (2015)[5] J.O. Thurgood, D. Tsiklauri, J. Plasma Phys. vol. 82, 905820604 (2016)

83

APSPM 2017
Session 3: Flare, ejection and space weather

CME kinematics and geoeﬀectiveness
Abstract Author(s): Nat Gopalswamy
Institution(s): NASA Goddard Space Flight Center
Presentation: O3 029K
Abstract
Coronal mass ejections (CMEs) are one of the major sources of space weather
because they cause solar energetic particle (SEP) events and major geomagnetic storms. While SEP acceleration depends on the shock-diving capability ofCMEs, geomagnetic storms depend on the magnetic structure of CMEs and/or
the shock sheath. In particular, the CME magnetic field needs to have a southward component that reconnects with Earths magnetic field. Both the space
weather phenomena depend on CME kinematics: fast and wide CMEs drive
shocks and carry intense magnetic fields. When CMEs attain high speeds isalso important: high-speeds near the Sun (within a couple of solar radii) resultsin shock formation in high magnetic field regions, leading to eﬃcient acceleration of CMEs. On the other hand CMEs remaining fast close to Earth resultin intense geomagnetic storms, provided the magnetic field they carry has asouthward component. The magnetic and particle environment of CMEs canalso significantly aﬀect their space weather consequences. For example, CMEs
can be deflected towards and away from the Sun-Earth line that can enhanceor reduce the geoeﬀectiveness of CMEs. This talk will highlight the role playedby CME kinematics in understanding their space weather consequences.

84

APSPM 2017
Session 3: Flare, ejection and space weather

Observations of the CME shocks and the production of
SEPs
Abstract Author(s): Zigong Xu, Chuan Li
Institution(s): Nanjing University
Presentation: O3 030
Abstract
The acceleration mechanism of SEPs is still a hot debated problem especiallyduring the onset of large SEPs. Here, we present a case study on 2011-08-09
SEP event to clarify its acceleration source and an 3D statistical study including
19 SEPs in order to know where and how the particles are released. Based on
the remote-sensing and in-situ observations as well as the DSA theory, we foundthat the theoretical par-ticle spectrum was comparable to a observational one
and a weak correla-tion was obtained between the electrons producing HXR and
the in-situ observed electrons. These results indicated that the coronal shock
wave was the potential accelerator of SEPs. In statistical study, we obtained
the electrons and protons solar release and compare to the 3D CME struc-tures.
It is found the electrons are released 8 minutes earlier ( 0.5 Rs lower) than the
protons.

85

APSPM 2017
Session 3: Flare, ejection and space weather

The dynamic character of the solar wind, and its
implications for Solar Probe Plus and Solar Orbiter
Abstract Author(s): Hsiu-Shan Yu, B. V. Jackson, A. Buﬃngton, P. P. Hick
Institution(s): University of California
Presentation: O3 031
Abstract
Ulysses Solar wind observations show the polar regions to be uniform and nonstructured during solar minimum. However, as shown by analyzing LASCO C2and STEREO SECCHI COR2 coronagraph images, and using UCSD-developed
correlation-tracking techniques, the observed solar wind outflow is not a static
well-ordered motion, but instead shows highly-variable speed structures. The
high-speed polar structures are associated with slightly brighter (and also patchy)
coronal structures. When these patches are averaged with the slower surrounding corona, solar wind acceleration with distance is observed consistently acrossthe polar coronal hole regions. This acceleration with distance is also consistent
with the outward flow speed observed in polar regions determined from massflux considerations and coronagraph polarization brightness. The preliminarily results of the corona velocity determination using HI-1A images also reveal
the variable nature of the solar wind in the lower latitude regions. From thiswe conclude that Solar Probe Plus and Solar Orbiter will not only measurethese structures in-situ as a variable wind, but they may also determine the
key abundances and magnetic fields associated with these structures and how
these parameters relate to the solar wind acceleration seen in coronagraph andheliospheric observations.

86

APSPM 2017
Session 3: Flare, ejection and space weather

Project for Solar-Terrestrial Environment Prediction(PSTEP)
Abstract Author(s): Kanya Kusano
Institution(s): Nagoya University
Presentation: O3 033K
Abstract
Project for Solar-Terrestrial Environment Prediction (PSTEP) is a Japanesenation-wide research collaboration, which was launched with the support of a
Grant-in-Aid for Scientific Research on Innovative Areas from MEXT/Japan.
PSTEP aims to develop a synergistic interaction between predictive and scientific studies of the solar-terrestrial environment and to establish the basis fornext-generation space weather forecasting using the state-of-the-art observations
and the advanced physics-based modeling. In this paper, we will explain thebasic strategy of PSTEP and the new results of flare prediction study of PSTEP.
Recently, Ishiguro and Kusano (2017, ApJ) clarifies that the double-arc electric
current loop, which can be formed by the tether-cutting reconnection, can produce a new type of instability called double-arc instability (DAI). The stability
analysis of the DAI suggests that the new parameter kappa may represent thecritical condition of DAI. Therefore, we have analyzed the correlation of a newparameter kappa. Also, we analyzed the statistical property of magnetic twistof various active regions using SDO/HMI data and the nonlinear force-free field
extrapolation technique to devise a new way to evaluate the criticality of the
DAI. We will discuss the prospects of physics-based new flare prediction basedon those results.

87

APSPM 2017
Session 3: Flare, ejection and space weather

Development of space weather forecast models based on
statistics and deep-learning methods
Abstract Author(s): Yong-Jae Moon
Institution(s): Kyung Hee University
Presentation: O3 034I
Abstract
For the last decade, we have developed several space weather (solar flare, coronal mass ejections, solar proton event, and geomagnetic storm) forecast models
based on statistics. In this talk we will review our main results and discuss scientific implications. First, we have examined solar flare (R) and CME occurrence
probabilities depending on sunspot McIntosh classification, its area change, andsolar cycle phase. We find that sunspot area and its increase (a proxy of flux
emergence) greatly enhance solar flare and CME occurrence rates for several
sunspot classes. Second, we have developed a solar proton event (S) forecast
model depending on flare parameters (flare strength, duration, and longitude)
as well as CME parameters (speed and angular width). We find that solar proton event probability strongly depends on these parameters. Third, we havedeveloped an empirical storm (G) forecast model to predict the probability andstrength of a storm using halo CME-Dst storm data. Fourth, we have developed
a full ice-cream cone model for CME 3-D parameters using single coronagraphdata and found that the derived 3-D parameters are similar to those from stereoscopic methods using multi-spacecraft. Recently we are developing a set of flareoccurrence model based on deep learning methods such as convolution neuralnetwork using solar magnetograms and EUV images. These models show a very
remarkable improvement of skill scores relative to the conventional ones.

88

APSPM 2017
Session 3: Flare, ejection and space weather

Space weather forecast using background information
generated by superposed observations over previous
Carrington cycles
Abstract Author(s): Rok-Soon Kim, J.-Y. Park, J.-H. Baek, I.-H. Cho, B.-G.
Kim
Institution(s): Korea Astronomy and Space Science Institute, Kyung Hee
University, Chungnam National University
Presentation: O3 035
Abstract
It is well known that there are good relations of coronal hole (CH) parameterssuch as the size, location, and magnetic field strength to the solar wind conditions and the geomagnetic storms. Especially in the minimum phase of solar cycle, CHs in mid- or low-latitude are one of major drivers for geomagnetic storms,
since they form corotating interaction regions (CIRs). Space Weather ResearchCenter (SWRC) in Korea Astronomy and Space Science Institute (KASI) has
done daily forecast of solar wind speed and Dst index from 2010. Throughyears of experience, we realize that the geomagnetic storms caused by CHs havediﬀerent characteristics from those by CMEs. Therefore, we analyze the characteristics and causality of the geomagnetic storms by the CHs and solar activities
statistically. As the results, we show the diﬀerent trends of the solar wind parameters and geomagnetic indices depending on the degree of solar activities
and suggest space weather forecast using background information generated bysuperposed observations over previous Carrington cycles to improve forecasting
capability.

89APSPM 2017
Session 3: Flare, ejection and space weather

Evidence of electron cyclotron maser emission at
decimetric frequency: First high cadence GMRT
observations
Abstract Author(s): Susanta Kumar Bisoi, H. S. Sawant, P. Janardhan, Y.
Yan, L. Chen , S. Srivastava, G. Gao
Institution(s): National Astronomical Observatories, National Institute forSpace Research, Physical Research Laboratory, Yunnan Observatories
Presentation: O3 036
Abstract
We report, for the first time, an investigation of solar flare activity, using highcadence (0.5 s) observations at the frequency of 610 MHz with the Giant Meterwave Radio Telescope (GMRT), India. We mapped all the radio burst eventsat GMRT/610 MHz associated with the two solar flares (a C1.4 and a M1.0
flare), that erupted on 20 June 2015, and a coronal mass ejection (CME) aftermath the M1.0 flare. Strong 610 MHz radio bursts were identified, near theflaring active region, during the M1.0 flare maximum and after the onset of the
CME. In contrast, during the C1.4 flare maximum, a strong 610 MHz radio
burst was rather identified near the south-east solar limb, located far away fromthe flaring active region, where no corresponding coronal features were seen.
The 610 MHz limb radio burst showed a good temporal correspondence with ametric type-III burst as identified by the Solar Broadband Radio Spectrometerat Yunnan Astronomical Observatory (SBRS/YNAO), China. We carried out amulti-wavelength analysis to locate source regions of both decimetric and metricbursts, and also found that the decimetric bursts were produced by the electron
cyclotron maser emission process in opposite to the generally observed coherent
plasma emission process at 610 MHz.

90

APSPM 2017
Session 3: Flare, ejection and space weather

The First ALMA Observation of a Solar Plasmoid
Ejection from an X-Ray Bright Point
Abstract Author(s): Masumi Shimojo, Hugh S. Hudson, Stephen M. White,
Timothy S. Bastian, Kazumasa Iwai
Institution(s): National Astronomical Observatory of Japan , Grasgow University, AFRL, NRAO, Nagoya University
Presentation: O3 037
Abstract
Eruptive phenomena are important features of energy releases events, such solar
flares, and have the potential to improve our understanding of the dynamics ofthe solar atmosphere. The 304 A EUV line of helium, formed at around 105
K, is found to be a reliable tracer of such phenomena, but the determinationof physical parameters from such observations is not straightforward. We haveobserved a plasmoid ejection from an X-ray bright point simultaneously with
ALMA, SDO/AIA, and Hinode/XRT. This paper reports the physical parameters of the plasmoid obtained by combining the radio, EUV, and X-ray data.
As a result, we conclude that the plasmoid can consist either of (approximately)isothermal ∼105 K plasma that is optically thin at 100 GHz, or a ∼104 K corewith a hot envelope. The analysis demonstrates the value of the additionaltemperature and density constraints that ALMA provides, and future scienceobservations with ALMA will be able to match the spatial resolution of spaceborne and other high-resolution telescopes.

91

APSPM 2017
Session 3: Flare, ejection and space weather

Sigmoidal Hot Channel Before Solar Eruptions
Abstract Author(s): Jeongwoo Lee, Bernhard Kliem, Stephen M. White,
Chang Liu, Satoshi Masuda
Institution(s): Seoul National University, University of Potsdam, Air Force
Research Laboratory, New Jersey Institute of Technology, Nagoya University
Presentation: O3 038
Abstract
We present an excellent piece of evidence that a flux rope can exist before aflare in the form of hot channel as found from the observations of the 2015
June 21 flare with the Solar Dynamics Observatory (SDO) and the Nobeyama
Radioheliograph (NoRH). The SDO EUV images and the extrapolated nonlinear
force-free field show that the impulsive flare results from the eruption of highly
sheared low-lying flux and remains confined, but nevertheless spawns a verticalcurrent sheet, where magnetic reconnection creates flare ribbons and loops anda sigmoidal hot channel. Until the second gradual flare, magnetic reconnection
continues at a low rate and the sigmoid’s elbows expand, while its center remains
stationary under the erupted but still confined flux. The reconnection during
and after the confined flare acts as tether-cutting reconnection, leading theflux rope to the point of instability and subsequent full eruption, seen as anaccelerated rise of the entire hot channel and the formation of a fast halo coronalmass ejection (CME). The hot channel can only be interpreted as a magnetic
flux rope, and this event is one of the clearest cases so far showing the existenceof a flux rope prior to an eruption.

92

APSPM 2017
Session 3: Flare, ejection and space weather

Superflares on Solar Type Stars
Abstract Author(s): Daisaku Nogami
Institution(s): Kyoto University
Presentation: O3 040I
Abstract
Superflares are defined as flares which are over 10 times more energetic (> 1033
erg) than largest flares ever observed on the Sun, and many superflares have beenfound on many solar-type stars, i.e. G-type main sequence stars in the Keplerspacecraft data. Statistical analyses indicate that the frequency distribution
to the flare energy of the superflare is almost consistent with that of the Sun.
Many of superflare stars show quasi-periodic variations with timescales of about
1 to 30 days. Spectroscopic measurements of the projected rotation velocity
suggest that these variations are due to rotation of superflare stars with largestarspots. The size distribution of starspots shows the power-law distribution
which is on the same line of the size distribution of relatively large sunspots. The
frequency-energy distributions for flares originating from spots with diﬀerent
sizes are the same for solar-type stars with superflares and the Sun. These
results suggest that the magnetic activity on solar-type stars with superflares
and that on the Sun is caused by the same physical processes. Long termmonitoring of the chromospheric activity and research on possible coronal massejections accompanying with superflares will give us an insight on the eﬀects ofsuperflares on the planetary environment, and possible extreme space weather
events on the Earth.

93

APSPM 2017
Session 3: Flare, ejection and space weather

Spectroscopic observations of solar-type superflare stars
Abstract Author(s): Yuta Notsu, Hiroyuki Maehara, Suzanne Hawley, Satoshi
Honda, Shota Notsu, Kosuke Namekata, Kai Ikuta, Daisaku Nogami,
Kazunari Shibata
Institution(s): Kyoto University, National Astronomical Observatory of Japan, University of Washington, University of Hyogo
Presentation: O3 041
Abstract
Superflares are flares that release total energy 10-104 times greater than thatof the biggest solar flares (∼1032 erg). Recent Kepler-space-telescope observations found more than 1000 superflares on a few hundred solar-type stars. Suchsuperflare stars show quasi-periodic brightness variations. Rotation period andstarspot coverage can be estimated from these brightness variations. However,spectroscopic observations are needed to investigate whether the variation isreally due to the rotation, and whether superflares can occur on ordinary single
stars similar to our Sun. Then we have carried out spectroscopic observations for
65 solar-type superflare stars with Subaru/HDS and Apache Point Observatory
3.5m telescope. As a result, more than half of the target stars show no evidenceof binarity, and the atmospheric parameters are in the range of solar-type stars.
The detailed analyses show that (1) the projected rotational velocities (v sin i)are consistent with the rotational velocities estimated from the brightness variations, (2) there is a correlation between the brightness variation amplitude andthe intensity of Ca II lines. In particular, the latter correlation suggests thatas for starspot coverage, results from Kepler and those from spectroscopic observations are consistent. These support that the brightness variation discussed
above is explained by the rotation of a star with large starspots.

94

APSPM 2017
Session 3: Flare, ejection and space weather

Statistical Study of Solar White-light Flares andComparisons with Superflares on Solar-type Stars
Abstract Author(s): Kosuke Namekata, Takahito Sakaue, Kyoko Watanabe,
Ayumi Asai, Hiroyuki Maehara, Yuta Notsu, Satoshi Honda, Shota Notsu,
Takako T. Ishii, Kai Ikuta, Daisaku Nogami, Kazunari Shibata
Institution(s): Kyoto University, National Defense Academy of Japan, National Astronomical Observatory of Japan , University of Hyogo
Presentation: O3 042
Abstract
Recently, many superflares on solar-type stars have been discovered as whitelight flares. The statistical study found a correlation between their energies (E)and durations (t): t ∝ E 0.39 , similar to those of solar hard/soft X-ray flares:t ∝ E 0.2−0.33 . This indicates a universal mechanism of energy release on solar
and stellar flares, i.e., magnetic reconnection. We here carried out a statisticalresearch on 50 solar white-light flares with SDO/HMI and examined the correlation between the energies and durations. As a result, the t-E relation on solar
white-light flares (t ∝ E 0.42 ) is similar to that on stellar superflares (t ∝ E 0.39 ).
However, the durations of stellar superflares are one order of magnitude shorter
than those expected from solar white-light flares. We present the following two
interpretations for the discrepancy. (1) In solar flares, the cooling timescale ofwhite light may be longer than the reconnection one, and the decay time of solar
white-light flare can be determined by the cooling time. (2) The distribution
can be understood by applying a scaling law (t ∝ E 1/3 B −5/3 ) derived from themagnetic reconnection theory. In this case, the observed superflares is expected
to have 2-4 times stronger magnetic field strength than solar flares.

95

APSPM 2017
Session 3: Flare, ejection and space weather

Continuum emission from solar flares
Abstract Author(s): Petr Heinzel
Institution(s): Czech Academy of Sciences
Presentation: O3 043
Abstract
I will review recent advances in observations and modeling of the continuum
emission from solar flares. In the optical range the continuum enhancement
is traditionally called the white-light flare (WLF), and depending on the particular flare, the WLF intensity may consist of both the photospheric as well
as chromospheric components. The latter one manifests itself also in the blue
part of the spectrum, behind the Balmer limit at 364.6 nm. Despite of many
attempts, the Balmer continuum was hard to detect from the ground and only
a few decisive detections exist. However, recent flare observations by IRIS in
its NUV channel have revealed a significant continuum enhancement which wasinterpreted as the hydrogen Balmer recombination continuum. In the opticalrange, Paschen recombination continuum should thus be also detectable. On
the other hand, recent SDO/HMI detection of the WLFs above the limb seems
to be due to Paschen-continuum emission. I will also present recent radiationhydrodynamical (RHD) models of the electron-beam heated flares, computedwith the FLARIX code developed at the Ondrejov Observatory. Numericalsimulations show that at the flare peak the radiation losses from the chromosphere are dominated by the Balmer continuum and thus a reliable detectionof this continuum (and Paschen one) represents a strong constraint on the flaremodeling and diagnostics.

96

APSPM 2017
Session 3: Flare, ejection and space weather

Recent scientific results of 1 m New vacuum solar
telescope at Fuxian Lake Observatory
Abstract Author(s): Xiaoli Yan
Institution(s): Yunnan Observatories
Presentation: P3 040
Abstract
One-metre New Vacuum Solar Telescope (NVST) located at the Fuxian Lakesolar observatory of Yunnan Observatories is one of three observational systems
that can observe fine structure of the Sun in the world. It is a largest solar
telescope in China. Its space resolution is better than 0.2 arc-seconds and time
resolution can reach one second. This telescope can observe diﬀerent layers of
the Sun, e.g., photosphere, chromosphere. In recent year, a series of original andinnovative results are obtained on the small-scale activities and fine structure ofsolar atmosphere based on NVST data. In this talk, I will present several new
results on small-scale magnetic reconnection, filament formation and eruptions
observed by NVST.

97

APSPM 2017
Session 3: Flare, ejection and space weather

The FMT at KSU as part of the CHAIN project withpreliminary results
Abstract Author(s): Ahmed Ibrahim, S. UeNo, Mohamad Elnawawy, Mohmad
Rezk, Ayman Kordi, Husen Trabulsy, Aboazza Elmohammadi
Institution(s): King Saud University, Kyoto University
Presentation: P3 041
Abstract
A new flare monitoring telescope (FMT) is installed at King Saud University(KSU), Kingdom of Saudi Arabia since November 2015. This telescope is themost recent contributor to the CHAIN project. It is a worldwide project aims to
make continuous H-alpha imaging network. There are three members contributein this project: one at Hida. The Solar Magnetic Activity Research Telescope(SMART) in Japan, the second FMT at Peru and our FMT is the third a possible
fourth one is planned in Algeria. The FMT can be used to investigate many ofthe explosive solar activity in particular flare events. The FMT has five solar
imaging telescopes that observe simultaneously the full solar disk at diﬀerent
wavelengths plus or minus the central H-alpha absorption line. Hence the FMT
can be useful to get three-dimensional results of the velocity of the moving
events during its evolution on the solar disk. It is hope to be able to monitor
solar flare events and the other erupting solar phenomena and investigate theircorrelation with CME and their impact on the space weather. Using our FMT
we were able to get solar observations for more than one year from November
2015 to Nov. 2016. The most interesting raw data results are presented.

98

APSPM 2017
Session 3: Flare, ejection and space weather

A Circular White-Light Flare with Impulsive and GradualWhite-Light Sources
Abstract Author(s): Qi Hao, Kai Yang, Xin Cheng, Yang Guo, Cheng Fang,
Mingde Ding, Pengfei Chen, Zhen Li
Institution(s): Nanjing University
Presentation: P3 042
Abstract
Solar flares are one of the most energetic eruptive events in the solar systemthat have a great impact on space weather. White-light flares are the flaresthat have emissions visible in the optical continuum. They are thought to berare and among the most energetic flaring events, which pose the most stringent
requirements in energy transport and heating in the lower atmosphere. Here wefor the first time report a rare circular white-light flare that occurred on 2015
March 10 and was well observed by the Optical and Near-infrared Solar Eruption Tracer (ONSET) and Solar Dynamics Observatory(SDO). The white-lightemission of the flare consists of two components, one being impulsive and closely
following the impulsive increase of the hard X-ray (HXR) flux, and the otherbeing gradual without obvious HXR sources. Especially, the gradual source isa new finding, which requires a mechanism other than the bombardment by anelectron beam as in the classical model. A possible mechanism is the quasiseparatrix layer reconnection or the large-scale Alfven waves transporting theenergy from the reconnection site to the lower atmosphere.

99

APSPM 2017
Session 3: Flare, ejection and space weather

A white-light flare triggered by flux emergence in NOAA
active region 11476
Abstract Author(s): Yongliang Song, Hui Tian
Institution(s): Peking University
Presentation: P3 043
Abstract
We report a white-light flare SOL2012-05-10T04:11 (M5.7) in NOAA active region 11476. Using data from SDO, ONSET, NoRH, RHESSI and GOES, we
investigated the relationship between the white-light enhancement and emissionof hard X-ray and microwave. Our result supports the back-warming model.
Just prior to the flare, we found clear evidence of flux emergence at the location of the white light enhancement. We also reconstructed the magnetic field
configuration before the flare through a nonlinear force-free field (NLFFF) extrapolation method, and found a fan-spine topology. Reconnection in such a
topology may be responsible for the occurrence of this white light flare.

100

APSPM 2017
Session 3: Flare, ejection and space weather

Cold Solar Flares Observed with Nobeyama
Radioheliograph
Abstract Author(s): Satoshi Masuda
Institution(s): Nagoya University
Presentation: P3 044
Abstract
When a solar flare takes place, magnetic energy is impulsively released, and it
is converted to other kinds of energy such as thermal energy (plasma heating),
kinetic energy (mass ejection), and energy of high-energy particles (particle
acceleration). The ratio of these three energies seems diﬀerent in each solar flare.
What controls the energy conversion ratio? In order to solve this problem, oneof the eﬀective ways is an analysis of some extreme flares such as thermal-richflares and purely nonthermal flares. Then, we focused on so-called cold flare
which shows significant nonthermal emissions with relatively very small amountof thermal emissions. A case study was done for a cold solar flare occurringon 10 March 2011 observed with Nobeyama Radioheliograph (Masuda et al.
2013). The characteristics of this flare were short duration and very compact
size. From these facts, we concluded that the magnetic field of the loop top
region might be very intense. To confirm this, we analyzed a few additional
cold flares. Their characteristics seem to be the same as the previous event. We
discuss how cold flares are produced based on this result.

101

APSPM 2017
Session 3: Flare, ejection and space weather

The transition from circular to nonstandard two-ribbon
flares due to magnetic flux ropes bifurcation
Abstract Author(s): Ze Zhong, Yang Guo, Mingde Ding
Institution(s): Nanjing University
Presentation: P3 045
Abstract
Magnetic flux ropes play a key role in understanding solar flares in the solar
atmosphere. In this work, we investigate the magnetic field structure of active
region NOAA 12268 over thirty six hours from 2015 January 29 to 30, during which time three M-class and three C-class flares were triggered withoutcoronal mass ejections (CMEs). With the evolution of the active region, theultraviolet emissions displayed the flare ribbons were transformed from the circular to the multiple ribbons. We find a two-stage progress from a series ofthree-dimensional nonlinear force-free field with boundary conditions using thevector magnetic field data observed by the Helioseismic and Magnetic Imager.
In the first stage, sheared arcades transformed into flux ropes through magnetic
reconnection. And then, the flux ropes began to bifurcate with the appearanceof multi-ribbon flares. The twist of the flux ropes gradually accumulated andeventually led to instability. We also identify that a large-scale quasi-separatrix
layer (QSL) associated with three-dimensional null points by the quadrupolar
magnetic field always existed stably during thirty six hours and another three
topological structures coexisted when the flux ropes took shape: bald patch,
hyperbolic flux tube and QSL around the flux rope. All these topological structures explain the behavior of the flares.

102

APSPM 2017
Session 3: Flare, ejection and space weather

Explosive Chromospheric Evaporation Driven by
Nonthermal Electrons around One Footpoint of a Solar
Flare Loop
Abstract Author(s): Dong Li
Institution(s): Purple Mountain Observatory
Presentation: P3 046
Abstract
We explore the temporal relationship between microwave/hard X-ray (HXR)
emission and Doppler velocity during the impulsive phase of a solar flare on
2014 October 27 (SOL2014-10-27) that displays a pulse on the light curves in
the microwave (34 GHz) and HXR (25-50 keV) bands before the flare maximum.
Imaging observation shows that this pulse mainly comes from one footpoint ofa solar flare loop. The slit of the Interface Region Imaging Spectrograph (IRIS)
stays at this footpoint during this solar flare. The Doppler velocities of Fe XXI
1354.09 Å and Si IV 1402.77 Å are extracted from the Gaussian fitting method.
We find that the hot line of Fe XXI 1354.09 Å (log T ∼ 7.05) in the corona
exhibits blueshift, while the cool line of Si IV 1402.77 Å (log T ∼ 4.8) in thetransition region exhibits redshift, indicating explosive chromospheric evaporation. Evaporative upflows along the flare loop are also observed in the AIA 131
Å image. To our knowledge, this is the first report of chromospheric evaporation
evidence from both spectral and imaging observations in the same flare. Bothmicrowave and HXR pulses are well correlated with the Doppler velocities, suggesting that the chromospheric evaporation is driven by nonthermal electrons
around this footpoint of a solar flare loop.

103

APSPM 2017
Session 3: Flare, ejection and space weather

Case study of chromospheric evaporation at flare ribbons
by IRIS
Abstract Author(s): Yu Chen
Institution(s): National Central University
Presentation: P3 047
Abstract
Chromospheric evaporation is thought to be the consequence of energy deposition on the chromosphere leading to the plasma expansion into the flaring loop.
In general, the evaporation can be classified into the explosive type which isdriven by non-thermal electron beam and the gentle type due to thermal conduction. We would like to characterize the evaporation flow at flare ribbons
based on the imaging and spectral data of IRIS. The velocity of plasma flows
is retrieved from a single or double Gaussian fitting to the profiles of Fe XXI
and Si IV emission lines. By combining with the SDO/AIA and RHESSI observations, we will also discuss the temporal correlation with X-ray lightcurves,the spatial correspondence with X-ray sources, and the consistency of Neuperteﬀect in our studied events.

104

APSPM 2017
Session 3: Flare, ejection and space weather

Apparent Motion of Flaring Ribbons Observed by
SDO/AIA
Abstract Author(s): Yun-Chen Yang, Ya-Hui Yang
Institution(s): National Central University
Presentation: P3 048
Abstract
To understand the role of magnetic reconnection on flare evolution, we investigate the apparent motions of two-ribbon structures seen in SDO/AIA 1600
Å images systematically. The M- and X-class flares with clear two ribbons
straddling the magnetic polarity inversion lines (PILs) with relatively simple
configuration are selected in this study. We estimate the motion speed along
the corresponding PIL (namely, Vpara) and the separation speed away from the
PIL (namely, Vper). We attempt to characterize the evolution of reconnection
or energy release process during major flares by examining diﬀerent types ofribbon motions statistically. The comparison with other flare-related signatures
will also be discussed.

105

APSPM 2017
Session 3: Flare, ejection and space weather

Spectroscopic observation of a loop-top source of an M1.3
limb solar flare
Abstract Author(s): Kyoung-Sun Lee, Hirohisa Hara, Shinsuke Imada, Kyoko
WatanabeInstitution(s): National Astronomical Observatory of Japan, Nagoya University, National Defense Academy
Presentation: P3 049
Abstract
We have investigated an M1.3 flare on 2014 January 13 around 21:48 UT observed at the west limb using the Hinode, SDO, and STEREO. Especially, theHinode/EIS scanned the flaring loop covering the loop-top region over the limb,
which is a good target to investigate the dynamics of the flaring loop with
their height. Using the multi-wavelength observations from the Hinode/EIS
and SDO/AIA, we found a very hot emission above the loop-top observed in Fe
XXIV (94Å channel). Measuring the intensity, Doppler velocity and line width
for the flaring loop, we found that hot emission observed at the cusp like shapeof loop-top region which shows strong redshift about 500 km/s and strong enhancement of the non-thermal velocity (line width enhancement) larger than
100 km/s. Combining with the STEREO observation, we also discuss the 3D
structure and velocity distribution of the loop-top region.

106

APSPM 2017
Session 3: Flare, ejection and space weather

Observational Analysis of the Fine Structure andFormation of Solar Jets
Abstract Author(s): Yuandeng Shen
Institution(s): Yunnan Observatories
Presentation: P3 050
Abstract
Solar jets are heated plasma moving along open magnetic field lines, they havelinear structures and usually associated with magnetic flux emergences and cancellations, micro-flares, and coronal mass ejections. Recent high temporal andspatial resolution data taken by SDO and NVST revealed a lot of new characteristics about the fine structure and formation mechanism of solar jets. This talkwill briefly introduce some of our studies on the solar jets using the SDO and
NVST observations, in which we studied the driving mechanism, fine structure,and their relations with mini-filament eruptions and coronal mass ejections.

107

APSPM 2017
Session 3: Flare, ejection and space weather

Properties of quasi-periodic pulsations in solar flares froma single active region
Abstract Author(s): Chloe E. Pugh, Valery M. Nakariakov, Anne-Marie Broomhall
Institution(s): University of Warwick
Presentation: P3 051
Abstract
Quasi-periodic pulsations (QPPs) have been found to be a common phenomenon
in solar flares, and recent exoplanet surveys are also increasing the number ofobservations of stellar superflares showing QPPs. The growing number of highquality flare observations means that statistical studies of QPPs in flares can beundertaken with the aim of better understanding this mysterious phenomenon.
In this study we search for QPPs in a set of 181 solar flares from a single longlived active region (NOAA 12192), making use of a highly robust method that
accounts for data uncertainties and the possible presence of red noise. When applied to X-ray and microwave data from GOES, SDO/EVE, Fermi, Vernov andNobeyama Radioheliograph this method reveals statistically significant QPP
signals in 20% of the flares. We find no correlation of the QPP periods withactive region properties determined using magnetogram data from SDO/HMI,
suggesting that diﬀerent QPP mechanisms act in diﬀerent cases and/or that thesmall-scale structure of the flaring region is important.

108

APSPM 2017
Session 3: Flare, ejection and space weather

Analysis of Sunspot Proper Motion related to X-Class
Solar Flare
Abstract Author(s): Lilis Mubasaroh
Institution(s): Bandung Institute of Technology
Presentation: P3 052
Abstract
Sunspots proper motion are the motion that already happen within correction
from Solar diﬀerential rotation. This proper motion may can influence the phenomena in outer solar athmosphere, such as Solar flare. Flares occur suddenly
when there are magnetic field reconnection that rooted from inner Solar atmosphere and rise until corona. Multi-wavelength observation has shown thatsome of Solar activity in corona increase significanly when the sunspot groups
have complex form and rapid motions. This study will explain the analysis ofsunspot proper motion in sunspot group during X-class Solar flare, measure its
linear velocity, and construct the magnetic polarity of this sunspot gorup duringobservational time. X-class flare choosed because this flare have chance to beobserved as white-light solar flare. Data used for this study was from SDO/HMI
instruments which in continuum and magnetogram archive. This analysis havegoal for flare prediction from knowing the sunspot activity such sunspots propermotion.

109

APSPM 2017
Session 3: Flare, ejection and space weather

Emergence Process of the Satellite Spots Leading to theSuccessive Flares
Abstract Author(s): Takahito Sakaue, Akiko Tei, Ayumi Asai, Satoru Ueno,
Kiyoshi Ichimoto, Kazunari Shibata
Institution(s): Kyoto University
Presentation: P3 053
Abstract
We report the successive flares on 2014 November 10. They were involved withthe satellite spots emergence around a delta-type sunspot in the decaying active
region NOAA 12205. The satellite spots have been examined as the activatorof an evolved active region, but there remain questions on their formation andconnectivity with the associated pivotal sunspot. Further studies are needed tocomprehend the process from the birth of the satellite spots to the explosive phenomena associated with them. Thanks to the continuous full-disk observationby the Solar Dynamics Observatory, we were able to investigate these explosive
phenomena in terms of their energy build-up, event trigger, and energy release
phases. In particular, this study (Sakaue et al. 2017, accepted by PASJ) focuses on the energy build-up and trigger phases, by analyzing the photospherichorizontal flow field around the active region with an optical flow method. The
analysis reveals that: (1) The observed explosive phenomena involved threesatellite spots, the magnetic fluxes of which successively reconnected with theirpre-existing ambient fields. (2) All of these satellite spots emerged in the moat
region of a pivotal delta-type sunspot, especially near its convergent boundarywith the neighboring supergranules or moat regions of adjacent sunspots.

110

APSPM 2017
Session 3: Flare, ejection and space weather

On the relationship between the rapid penumbra
formation and impulsive flare in NOAA12403
Abstract Author(s): Shin’ichi Nagata
Institution(s): Kyoto University
Presentation: P3 054
Abstract
We observed an M5.6 flare occurred on 24-Aug-2016 at NOAA12403 with thetandem etalon magnetograph of the Solar Magnetic Active Research Telescope(SMART) of Hida observatory. The impulsive EUV brightness enhancement wasobserved with the all channels of the Atmospheric Imaging Assembly (AIA) on
the Solar Dynamics Observatory (SDO). The enhancement was found aroundthe following spot of this active region where no clear penumbra seen before
the flare. We analyzed HMI data and found that appearance of penumbra after
the impulsive flare. On the other hand, we find the horizontal photosphericmagnetic field enhancement in the SMART magnetic field data with time scaleof several minutes just after the flare. Based on the observed rapid evolution of
penumbra and magnetic fields, we discuss the topological change of the magnetic
field associated with the impulsive flare.

111

APSPM 2017
Session 3: Flare, ejection and space weather

Evolution of Coronal Jets on the Solar Limb based on
SDO/AIA Images Datas
Abstract Author(s): Herna Fahriyah, Dhani Herdiwijaya
Institution(s): Institute of Technology Bandung
Presentation: P3 055
Abstract
Solar Jets are the typical collimated and transient ejecta in the solar atmospherethat is significant in mass and energy transport at various spatial and temporalscales. Jets are ubiquitous events that have the various type of morphology andcomplex evolution due to magnetic fields structure. This study shows physicalcharacteristics (the heights and the apparent velocities) and temporal evolution using SDO/AIA 304Å (log T=4.7 K), 171Å (log T=5.8 K), and 211Å (log
T=6.3 K) images data. They have a typical height of 68.000-160.000 km and an
apparent velocity of 16,7-455,6 km/s. Each of jet was ejected from the active region and quiet region showed diﬀerent characteristics. Generally, the strongest
contrast of the jets on 304Å and the weakest on 211Å. Magnetic reconnection
occurred in several times of jet lifetime as a reflection of magnetic fields structure complexity. Thus, this study presents an additional illustration showing
how huge canopy magnetic impede plasma flow on the open magnetic fields line.

112

APSPM 2017
Session 3: Flare, ejection and space weather

The formation of an active-region filament: the material
by jets
Abstract Author(s): Jincheng Wang, Xiaoli Yan
Institution(s): Yunnan Observatories
Presentation: P3 056
Abstract
We presented the formation process of a filament in active region NOAA 12574
during the period from August 11 to 12, 2016. Combining the observations of
GONG Ha and SDO/AIA 304 A, the complete process of filament formation was
exhibited. It was found that a lot of cool materials were directly lifted into thecorona by a serious of jets nearby the right foot-point of filament and became thefilament materials. Simultaneously, the magnetic flux emergence was found on
the photosphere below the right foot-point of the filament. These suggested thatcool materials in the low atmosphere can be directly injected into the filamentin the corona and jets would be caused by the magnetic reconnection throughthe interaction of pre-existed magnetic fields and new emergence magnetic fields.
Studying on a jet at 18:02 on Aug 11 in detail with NST/BBSO Tio observations,
it was found that the dark threads grew or emerged in the vicinity of the rightfoot-point after the jet and the transvers velocity of heated plasma along thefilament axis was about 157.6 km/s. On the other hand, by using Domeless Solar
Telescope observation at Hida observatory, we found that the injected plasmas
by a jet at 00:42 on Aug 12 were rotation. Therefore, we concluded that jets
not only forces the materials for the filament, but also injects the helicity into
the filament simultaneously.

113

APSPM 2017
Session 3: Flare, ejection and space weather

Recurrent Active region coronal jets: Examining themagnetic configuration of a persistent jet inducing
micro-flare site
Abstract Author(s): Alin Paraschiv, Alina Donea
Institution(s): Monash university
Presentation: P3 057
Abstract
Active region 11302 displayed an unusually large number of solar jets during
its lifetime. In search for a clue on the origin of these jets, we have analysed
the emission mechanism responsible for at least ten of the observed coronal jet
events, all occurring at the south-eastern penumbral boundary of the active region. The identified events were observed in extreme-ultraviolet and interesting
local features were correlated with corresponding low-lying magnetic features.
Our aim is to further understand this interaction process and assess jet properties from a data driven perspective. The accurate detection of local magnetic
field layout is essential. We use dedicated custom tools to accurately identify,
extrapolate, and visualise vertical field structures of the lower solar atmosphere.
The study lead to the discovery of a peculiar hot arched structure that expands
into the lower corona. We noticed the preference of low lying magnetic field lines
to cluster into this unique structure. We introduce the terminology ”Coronal
Geyser” to define the properties of this quasi-stable structure. The Geyser undergoes multiple reconnection events which account for all of the observed jets.
Recently, it was proposed that the heating of all base-arched structures and thejet emission are strongly linked to small-scale filament eruptions. The relation
between the jet origin and other dynamic plasma features, such as flaring, low
lying coronal loops, and twisted filaments, is amply discussed. Flux cancellations, dipole emergences, penumbral filaments and/or canopy fields embedded
in a dynamical moat penumbral region are all identified as playing a significant
role in fuelling the geyser structure.

114

APSPM 2017
Session 3: Flare, ejection and space weather

Type of magnetic null point and filament in the solar
atmosphere
Abstract Author(s): Huaning Wang, uan Guo, Xiaoshuai Zhu
Institution(s): National Astronomical Observatories
Presentation: P3 058
Abstract
Null points are most important topological features in solar magnetic field. A
type of null points with complex eigenvalue has twisted field lines along its
spine.This kind of topological features might be related to filaments in the solar
atmosphere. More than 14 solar active regions with filaments has been investigated and 12 of them have null points with complex eigenvalue.

115

APSPM 2017
Session 3: Flare, ejection and space weather

Magnetic Flux Rope: Topology and Twist Profile
Abstract Author(s): Rui Liu
Institution(s): University of Science and Technology of China
Presentation: P3 059
Abstract
Magnetic flux rope (MFR) is among the most fundamental magnetic configurations in plasma, and also a fundamental and key structure in solar eruptions,which are the dominant contributor to adverse space weather at Earth. In
this talk we will report our progress in the studies on MFRs erupting from theSun. By quantifying magnetic connectivities and magnetic twist, we are able
to identify MFRs as a 3D volume of enhanced magnetic twist, bounded by athin quasi-separatrix layer. Further, MFRs characteristics, including the distribution of magnetic twist within the rope, can be deciphered by combining themorphology and evolution of flare ribbons, post-eruptive dimmings, and in-situ
diagnostics.

116

APSPM 2017
Session 3: Flare, ejection and space weather

Increase in the amplitude of Line-of-sight velocities of thesmall-scale motions in a solar filament before eruption
Abstract Author(s): Daikichi Seki, Kenichi Otsuji , Hiroaki Isobe , Takako
T. Ishii, Takahito Sakaue , Kumi Hirose
Institution(s): Kyoto University
Presentation: P3 060
Abstract
We present a study on the evolution of the small-scale velocity field in a solar
filament as it approaches the eruption. The observation was carried out by
the Solar Dynamics Doppler Imager (SDDI) that was newly installed on the
Solar Magnetic Activity Research Telescope at Hida Observatory. The SDDI
obtains a narrowband full-disk image of the Sun at 73 channels from H-alpha 9.0 angstrom to H-alpha + 9.0 angstrom, allowing us to study the line-of-sight(LOS) velocity of the filament before and during the eruption. The observed
filament is a quiescent filament that erupted on 2016 November 5. We derived
the LOS velocity at each pixel in the filament using the Becker’s cloud model,
and made the histograms of the LOS velocity at each time. The standard
deviation of the LOS velocity distribution can be regarded as a measure for theamplitude of the small-scale motion in the filament. We found that it increased
with a rate of 2.8 m s−2 about an hour before eruption. From this result
we suggest that the increase in the amplitude of the small-scale motions in afilament can be regarded as a precursor of the eruption.

117

APSPM 2017
Session 3: Flare, ejection and space weather

Rapid eruptive phenomena observed by SMART/SDDI
and its influence to the interplanetary space
Abstract Author(s): Kenichi Otsuji
Institution(s): Kyoto University
Presentation: P3 061
Abstract
We observed a filament eruptive event which occurred on 2nd April 2017 byusing Solar Dynamics Doppler Imager (SDDI) on SMART in Hida observatory.
The eruption was associated with a M4.4 flare which took place at the solar
west limb and developed into the eruptive prominence. The observation was
done with a fast tunable filter which can take 73 wavelengths points with thestep of 0.25 Angstrom and the coverage of +/-9 Angstrom centered at H alphaline (6562.808 Angstrom). We apply the Beckers cloud model to the observed
dataset and derived the line of sight (LOS) velocity of the erupting prominence
blobs. We also measured the transversal (apparent) velocity of the blobs on theimage plane. We found that the erupting blobs have more than 100 km/s LOS
velocity and 500 km/s transversal velocity. Surprisingly we found an erupting
blob which seems to have near 1000 km/s transversal velocity. The erupted
prominence produces a CME. We will discuss the process of the eruption andits propagation in the interplanetary space.

118

APSPM 2017
Session 3: Flare, ejection and space weather

Investigation of a Large Ejective Solar Eruption from a
Typical Coronal-Jet-Base Field Configuration
Abstract Author(s): Navin Chandra Joshi, Alphonse C. Sterling, Ronald L.
Moore, Tetsuya Magara, Young-Jae Moon
Institution(s): Kyung Hee University, Marshall Space Flight Center
Presentation: P3 062
Abstract
We investigate a large-scale ejective solar eruption of 2014 December 18 from
active region NOAA 12241 using multi-wavelength observations and magnetic
field data from SDO/AIA, SDO/HMI, GOES and RHESSI. This event produced
a distinctive three-ribbon flare, having two parallel ribbons corresponding to theribbons of a standard two-ribbon flare, and a larger-scale third quasi-circularribbon oﬀset from the other two ribbons. There are two stages to this eruptive
event. First, a flux rope forms above a strong-field polarity-inversion line anderupts and grows as the parallel ribbons turn on, grow, and spread apart fromthat polarity-inversion line; this evolution is consistent with the tether-cutting
reconnection mechanism for eruptions. Second, the erupting arcade that has
the erupting flux rope in its core undergoes magnetic reconnection near the nullpoint of the fan dome that envelops the erupting arcade, resulting in formationof the quasi-circular ribbon; this is consistent with the breakout-reconnection
mechanism for eruptions. We find that the parallel ribbons begin about 12 min
before the circular ribbon onset, indicating that tether-cutting reconnection ora non-ideal MHD instability initiated this event, rather than breakout reconnection. The overall setup for this large-scale eruption is analogous to that ofcoronal jets.

119APSPM 2017
Session 3: Flare, ejection and space weather

Electron plasma wake field acceleration in solar coronaland chromospheric plasmas
Abstract Author(s): David Tsiklauri
Institution(s): Queen Mary University of London
Presentation: P3 063
Abstract
Three dimensional, particle-in-cell, fully electromagnetic simulations of electron
plasma wake field acceleration applicable to the solar atmosphere are presented[1]. It is established that injecting driving and trailing electron bunches into
solar coronal and chromospheric plasmas results in electric fields (−(20−5)×106
V/m), leading to acceleration of the trailing bunch up to 52 MeV, starting frominitial 36 MeV. The results provide one of the potentially important mechanisms
for the extremely energetic solar flare electrons, invoking plasma wake field
acceleration.
[1] D. Tsiklauri, Physics of Plasmas 24, 072902 (2017) doi: 10.1063/1.4990560

120

APSPM 2017
Session 3: Flare, ejection and space weather

MHD simulation of solar active region driven byobservation-inferred plasma motion and electric field
Abstract Author(s): Keiji Hayashi
Institution(s): National Space Science Center
Presentation: P3 064
Abstract
Solar active regions are consequences of evolving magnetic field and plasma injected through the solar photosphere. By applying time-series observation dataof solar photosphere to MHD simulation model, we in principle can trace thetemporal evolution of such magnetically complex system. We will show the results from our MHD simulation model that is recently re-developed for better
realistically simulating solar active region. The simulated active region system isdriven by either of plasma motion and electric field on the bottom boundary (orsolar surface) that are calculated from time-series vector magnetic field observation data taken by the SDO/HMI. The boundary treatment for six sub-Alfvenic
boundary surfaces is based on concept of characteristics, which helps minimize
mathematical and physical inconsistency. To mitigate computational diﬃculties
arising from extremely low-beta situations, we allowed somewhat high-density
situation as compromise. Many features, such as twisted field along magnetic
inversion lines and magnetic free energy comparable to a strong flare, are numerically obtained through this MHD model with time-dependent boundary
values.

121

APSPM 2017
Session 3: Flare, ejection and space weather

RADYN simulations of non-thermal and thermal models
of Ellerman bombs
Abstract Author(s): Jie Hong, Mats Carlsson, M.D. Ding
Institution(s): Nanjing University, University of Oslo
Presentation: P3 065
Abstract
Ellerman bombs (EBs) are brightenings in the H line wings that are believed
to be caused by magnetic reconnection in the lower atmosphere. To study the
response and evolution of the chromospheric line profiles, we perform radiativehydrodynamic simulations of EBs using both non-thermal and thermal models.
Overall, these models can generate line profiles that are similar to observations.
However, in non-thermal models we find dimming in the H line wings and continuum when the heating begins, while for the thermal models dimming occurs
only in the H line core, and with a longer lifetime. This diﬀerence in line profiles
can be used to determine whether an EB is dominated by non-thermal heating or thermal heating. In our simulations, if a higher heating rate is applied,the H line will be unrealistically strong, while there are still no clear UV burst
signatures.

122

APSPM 2017
Session 3: Flare, ejection and space weather

2.5D Particle-in-cell Simulation of Solar type III radio
burstsAbstract Author(s): Tangmu Li, Wenjun Ding, Chen P.F, Fang C
Institution(s): Nanjing University
Presentation: P3 066
Abstract
Solar type III radio bursts show quickly frequency drift. In this paper, the 2.5D
PIC method is used to simulate the fundamental frequency, harmonic radiationand mode conversion mechanism of the solar type III bursts caused by the
relativistic electron beam in the case of actually observing the density gradientand the initial magnetic field as the background.

123

APSPM 2017
Session 3: Flare, ejection and space weather

2.5 D particle-in-cell to simulate Coronal Particle
Acceleration of HeG3 / 4
Abstract Author(s): Wenjun Ding, Tangmu Li, Chen P.F , Fang C.
Institution(s): Nanjing University
Presentation: P3 067
Abstract
In this paper, we use particle in cell to explore the acceleration of He3 / He4 by acommon turbulence in the coronal plasma ,and was injected into the interstellar
acceleration process. When the relative abundance of He3 / He4 in the plasma
is enhanced, the mechanism can form a exponential power spectrum, which
provides a possible explanation for the correlation between the abundance of
He3 / He4 in the corona and the correlation between heavier particles.

124

APSPM 2017
Session 3: Flare, ejection and space weather

Relationship between the Occurrence of a Flare and the
Small-Scale Variation of Photospheric Magnetic Field in
Active Region 12371
Abstract Author(s): Jihye Kang, Tetsuya Magara, Yong-Jae Moon , Satoshi
Inoue
Institution(s): Kyung Hee University, Naogya University
Presentation: P3 068
Abstract
We investigate the flare productivity of a magnetic structure by focusing on
the spatial and temporal changes of photospheric magnetic field. The physicalprocess to develop a flare-producing magnetic structure in the corona in responseto these photospheric changes is one of the hot topics. We analyzed smallscale photospheric changes of observation data to see how they are related tothe occurrence of a flare. It is found that diﬀerence of transverse components
between potential field and observed photospheric vector field is noticeable ina small-scale emerging region near the main polarity inversion line in AR12371
when it produced an M-class flare. We also investigate a flare-producing coronalmagnetic configuration of this active region by using a nonlinear force-free fieldmodel.

125

APSPM 2017
Session 3: Flare, ejection and space weather

Evidence for a Magnetic Reconnection Origin of Plasma
Outflows along Post-CME Rays
Abstract Author(s): Jongchul Chae, Kyuhyoun Cho, Ryun-Young Kown,
Eunkyung-Lim
Institution(s): Seoul National University, APL, Korea Astronomy and Space
Science Institute
Presentation: P3 069
Abstract
Bright rays are often observed after coronal mass ejections (CMEs) erupt. Theserays are dynamical structures along which plasmas move outward. We investigated the outflows along the post-CME rays observed by the COR2 on board
STEREO Behind on 2013 September 21 and 22. We tracked two CMEs, two
ray tips, and seven blobs using the NAVE optical flow technique. As a result,
we found that the departure times of blobs and ray tips from the optimallychosen starting height coincided with the occurrence times of the corresponding
recurrent small flares within 10 minutes. These small flares took place many
hours after the major flares. This result supports a magnetic reconnection originof the outward flows along the post-CME ray and the importance of magnetic
islands for understanding the process of magnetic reconnection.

126

APSPM 2017
Session 3: Flare, ejection and space weather

Pre-eruption Oscillations in Quiescent Filament
Abstract Author(s): Anand D. Joshi, Yoichiro Hanaoka, Yoshinori Suematsu,
Satoshi Morita, Vasyl Yurchyshyn, Kyung-Suk Cho
Institution(s): National Astronomical Observatory of Japan, Korea Astronomy and Space Science Institute , Big Bear Solar Observatory, Universityof Science and Technology
Presentation: P3 070
Abstract
We investigate the eruption of a quiescent filament. Large-scale activation wasobserved in only half of the filament in the form of pre-eruption oscillations.
Consequently only this half erupted nearly 30 hr after the oscillations commenced. Time-slice diagrams of 171 Å images from the Atmospheric Imaging
Assembly on board the Solar Dynamics Observatory revealed that the oscillations occurred in several thin and long features connecting the filament spine
to the chromosphere below. This study traces the origin of such features andproposes their possible interpretation. Small-scale magnetic flux cancellationaccompanied by a brightening was observed at the footpoint of the features
shortly before their appearance, in images recorded by the Helioseismic andMagnetic Imager. A slow rise of the filament was detected when filament features were undergoing oscillations, indicating a gradual loss of equilibrium. Our
analysis using potential field model indicates that a change in magnetic field
connectivity between two neighbouring active regions and the quiescent filament resulted in a weakening of the overlying arcade of the filament, leading to
its eruption. It is also suggested that the oscillating features are filament barbs,
and the oscillations are a manifestation during the pre-eruption phase of thefilaments.

127

APSPM 2017
Session 3: Flare, ejection and space weather

Statistical Study of Active-region Microflares Observedwith Hinode/XRT
Abstract Author(s): Ryoya Uemura, Satoshi Masuda, Ryouhei Kano
Institution(s): Nagoya University, National Astronomical Observatory of Japan
Presentation: P3 071
Abstract
The microflare heating model is one of possible coronal heating mechanisms.
The frequency distribution of microflares as a function of their energy is important for evaluation of this model. It is reported as a result of Yohkoh/SXT
observations that the distribution was represented by a single power-law in theenergy range of 1027 - 1029 with an index of about -1.6 (Shimizu 1995). It
concluded that the total energy supplied by microflares and flares is not enoughto maintain the active-region corona even if this distribution is extended to thelower energy range. To investigate the frequency distribution below 1027 erg, weanalyzed high-cadence (3-6 sec) and high-resolution (1arcsec/pixel) soft X-ray
images of the active region NOAA10923 taken with Hinode/XRT with several
filters on November 13-14, 2006. We detected about 1000 enhancements in thelight curves of 4x4-pixel-binned XRT images in each filter period (20-30 min) as
microflares. The frequency distribution was represented by a power-law in therange of 1025 - 1027 erg, steeper than that with a power-law index of -2. This result indicates that, if the distribution has the same power-law index in the lower
energy range, microflares can supply suﬃcient energy required for active-region
coronal heating.

128

APSPM 2017
Session 3: Flare, ejection and space weather

Flare Productivity in Diﬀerent Magnetic Types of Active
Regions
Abstract Author(s): Ya-Hui Yang, Min-Shiu Hsieh, Hsiu-Shan Yu, Peng Fei
Chen
Institution(s): National Central University, University of Alaska Fairbanks,
University of California San Diego, Nanjing University
Presentation: P3 072
Abstract
Based on two datasets of daily sunspot and flare information as well as the
GOES soft X-ray measurements and HMI vector magnetograms, we investigate
the dependence of flare activity on the active region (AR) properties and clarify
the influence of AR magnetic parameters on the flare productivity. We find thatthe flare behaviors are quite diﬀerent in the short- and long-lived complex ARs.
Moreover, the ARs with more complex magnetic configurations are likely to hostmore impulsive and intense flares. Our results demonstrate that the total source
field strength on the photosphere has a good correlation with the flare activity
in complex ARs. Intense flares tend to occur at the regions of strong source fieldin combination with an intermediate field-weighted shear angle, which implies
that the magnetic free energy provided by a complex AR could be high enoughto trigger a flare even with a moderate magnetic shear on the photosphere. We
thus suggest that the magnetic free energy represented by the source field rather
than the photospheric magnetic complexity is a better quantity to characterize
the flare productivity of an AR, especially for the occurrence of intense flares.

129

APSPM 2017
Session 3: Flare, ejection and space weather

Statistical study on the radial and azimuthal wave modesof 24 Halo Coronal Mass Ejections using multi spacecraft
Abstract Author(s): Harim Lee, Yong-Jae Moon, V. M. Nakariakov
Institution(s): Kyung Hee University, University of Warwick
Presentation: P3 073
Abstract
We have made an investigation on the radial and azimuthal wave modes of full
halo coronal mass ejections (HCMEs). For this, we consider 24 HCMEs which
are simultaneously observed by SOHO and STEREO A & B from August 2010 toAugust 2012 when they were roughly in quadrature. Using the SOHO/LASCO
C3 and STEREO COR2 A & B running diﬀerence images, we estimate theinstantaneous apparent speeds of the HCMEs at 24 diﬀerent position angles.
Major results from this study are as follows. First, there are quasi-periodic
variations of the instantaneous radial velocity with the periods ranging from 24
to 48 mins. Second, the amplitudes of instant speed variations are about a thirdof the projected speeds. Third, the amplitudes are found to have a weak anticorrelation with period. Our preliminary identification from SOHO observations
shows that there are several distinct radial and azimuthal wave modes: m=0(radial) for five events, m=1 for eleven events, m=2 for three events, and unclear
for the other events. In addition, we are making a statistical investigation on
the oscillation of 733 CMEs to understand their physical origins.

130

APSPM 2017
Session 3: Flare, ejection and space weather

Transient Plasma Signatures and Space Weather
Abstract Author(s): Subhash C. KaushikInstitution(s): Government PG College ( Jiwaji University)
Presentation: P3 074
Abstract
One of the prime challenges for space weather researchers today is to quantitatively predict the dynamics of the geo-magnetosphere from measured solar
wind and interplanetary magnetic field (IMF) conditions. In the present study
a correlative study between geomagnetic storms and the various interplanetary(IP) field / plasma parameters have been performed to search the perpetratorsof geomagnetic activity and to develop such model suitable for predicting theoccurrence of geomagnetic storms, which are significant for space weather predictions. We investigated a possible relationship between geomagnetic storms
and solar wind and IMF parameters in diﬀerent situations and also derived thelinear relationship for all parameters in diﬀerent situations based on the peakvalues of Disturbance storm time index (Dst). The investigation is performed
utilizing the fact that the total interplanetary magnetic field (IMF Btotal) canbe used to trigger an intense geomagnetic storms well represented by the Dst
index. Our results inferred that the southward Bz component of the interplanetary magnetic field is an important factor for describing geomagnetic storms
however its magnitude is not found maximum neither during the initial phaseof the storm, i.e. at the instant of the interplanetary shock nor during the main
phase, the instant of minimum disturbance storm time (Dst) index. It is also
investigated that there is a time delay between the maximum value of southward
Bz and the Dst minimum, and this time delay can be used in the prediction of
the intensity of a magnetic storm two-three hours before the main phase of ageomagnetic storm.

131

APSPM 2017
Session 3: Flare, ejection and space weather

Solar Flare Forecast Model based on Convolutional Neural
Network using SOHO MDI Data and its Optimizations
Abstract Author(s): Eunsu Park, Yong-Jae Moon
Institution(s): Kyung Hee University
Presentation: P3 075
Abstract
A Convolutional Neural Network(CNN) is one of the well-known deep-learning
methods in image processing and computer vision area. In this study, we apply
CNN to two kinds of flare forecasting models: flare classification and occurrence.
For this, we consider several pre-trained models (e.g., AlexNet, GoogLeNet, andResNet) and customize them by changing several options such as the numberof layers, activation function, and optimizer. Our inputs are the same number
of SOHO)/MDI images for each flare class (None, C, M and X) at 00:00 UTfrom Jan 1996 to Dec 2010 (total 1600 images). Outputs are the results of daily
flare forecasting for flare class and occurrence. We build, train, and test themodels on TensorFlow, which is well-known machine learning software librarydeveloped by Google. Our major results from this study are as follows. First,
most of the models have accuracies more than 0.7. Second, ResNet developed byMicrosoft has the best accuracies : 0.86 for flare classification and 0.84 for flareoccurrence. Third, the accuracies of these models vary greatly with changing
parameters. We discuss several possibilities to improve the models.

132

APSPM 2017
Session 3: Flare, ejection and space weather

Forecast of Solar Major Flare Occurrence Rates Based on
Vector Magnetic Parameters Using SDO/HMI Data
Abstract Author(s): Daye Lim, Yong-Jae Moon , Jongyeob Park, Kangjin
Lee, Jin-Yi Lee
Institution(s): Kyung Hee University, Korea Astronomy and Space Science
Institute
Presentation: P3 076
Abstract
We investigate solar major (M and X-class) flare occurrence rates within a day
using hourly SHARP vector magnetic field data from May 2010 to April 2017.
We consider six SHARP parameters with high F-scores as useful predictors offlaring activity from Bobra and Couvidat (2015). We have considered two cases.
In case 1, the data divided into two sets separated chronologically. 75% of thedata are used for setting up a flare model and the other for test. In case 2, we
divide the data into two sets every year in order to reduce the solar cycle (SC)phase eﬀect. All magnetic parameters are divided into 100 groups to estimate
the corresponding flare occurrence rates. Flare identifications are determinedby using LMSAL flare locations. As a result, major flare occurrence rates arewell correlated with six parameters. We also find that the logarithmic values offlaring rates are well approximated by two linear equations with diﬀerent slopes.
The sum of the net current emanating from each polarity gives the minimum
RMS error between observed flare rates and predicted ones. The RMS error forcase 2, which is taken to reduce SC phase eﬀect, are smaller than those for case
1.

133

APSPM 2017
Session 3: Flare, ejection and space weather

Flare Forecast using Machine-learning ofMulti-wavelength Observations of Active Regions
Abstract Author(s): Naoto Nishizuka, Yuki Kubo, Komei Sugiura, Mitsue
Den, Sin-ichi Watari, Mamoru Ishii
Institution(s): National Institute of Information and Communications Technology
Presentation: P3 077
Abstract
We developed a flare prediction model using machine learning, which is optimized to predict the maximum class of flares occurring in the following 24 hr.
Machine learning is used to devise algorithms that can learn from and makedecisions on a huge amount of data. We used solar observation data during
the period 2010-2015, such as vector magnetograms, UV 1600A and soft X-ray
emissions taken by SDO and GOES. We detected active regions from the fulldisk magnetogram, from which 60 features were extracted, including magnetic
neutral lines, the current helicity, the UV brightening, and the flare history.
We separated the database into two for training and testing, and then we compared three machine-learning algorithms: the support vector machine, k-nearest
neighbors (k-NN), and extremely randomized trees. The prediction score, thetrue skill statistic, was higher than 0.9 with k-NN, which is higher than thatfor human forecasts. Furthermore, we investigated the ranking of the featureimportance. We found that previous flare activity is most eﬀective, followed by
the length of magnetic neutral lines, the unsigned magnetic flux, and the areaof UV brightening. This indicates that eﬀective features are strongly correlatedwith the flux emergence dynamics in an active region.

134

APSPM 2017
Session 3: Flare, ejection and space weather

Flare Occurrence Prediction based on Convolution Neural
Network and Comparison with Previous Models
Abstract Author(s): Kangwoo Yi, Yong-Jae Moon, Eunsu Park, Seulki Shin
Institution(s): Kyung Hee university
Presentation: P3 078
Abstract
In this study we apply Convolution Neural Network(CNN) to solar flare occurrence prediction with various parameter options using the 00:00 UT MDI
images from 1996 to 2010 (total 4962 images). We assume that only X, M andC class flares correspond to flare occurrence and the others to non-flare. We
have attempted to look for the best options for the models with two CNN pretrained models (AlexNet and GoogLeNet), by modifying training images andchanging hyper parameters. Our major results from this study are as follows.
First, the flare occurrence predictions are relatively good with about 80 % accuracies. Second, both flare prediction models based on AlexNet and GoogLeNet
have similar results but AlexNet is faster than GoogLeNet. Third, modifying
the training images to reduce the projection eﬀect is not eﬀective. Fourth, skill
scores of our flare occurrence model are mostly better than those of the previous
models.

135

APSPM 2017
Session 3: Flare, ejection and space weather

Starspot activity and superflares on solar-type stars
Abstract Author(s): Hiroyuki Maehara, Yuta Notsu, Shota Notsu, Kosuke
Namekata, Satoshi Honda, Takako T. Ishii, Daisaku Nogami, Kazunari
Shibata
Institution(s): National Astronomical Observatory of Japan , Kyoto University, University of Hyogo
Presentation: P3 079
Abstract
High-precision time-series photometry with the Kepler space telescope foundmore than 1000 ”superflares” on solar-type stars. The bolometric energy released by superflares ranges from 1033 erg to 1036 erg which is 10-104 times
larger than that released by a typical X10-class solar flare. Most of the stars
with superflares show large-amplitude photometric variations associated withthe stellar rotation which suggest that the stars with superflares have largestarspots. We analyzed the correlation between starspots and superflares on
solar-type stars using the data from the Kepler mission. Our analysis showsthat the fraction of the stars showing superflares decreases as the rotation period increases and as the area of starspots decreases. We found that the size
distribution of large starspots with the area of > 104 MSH (micro solar hemispheres; 1 MSH=3 × 1016 cm2 ) on slowly-rotating solar-type stars shows thepower-law distribution and both the size distribution of starspots on solar-typestars and that of larger sunspots are roughly on the same power-law line. We
also found that the frequency-energy distributions for flares originating fromspots with diﬀerent sizes are the same for solar-type stars with superflares andthe Sun. These results suggest that the magnetic activity on solar-type stars
with superflares and that on the Sun is caused by the same physical processes.

136

APSPM 2017
Session 3: Flare, ejection and space weather

Prediction of Solar Flares Using Unique Signatures ofMagnetic Field Images
Abstract Author(s): Abbas Raboonik, Hossein Safari, Nasibe Alipour, Michael
S. Wheatland
Institution(s): University of Mazandaran, University of Zanjan, The University of Sydney
Presentation: P3 080
Abstract
Prediction of solar flares is an important task in solar physics. The occurrence of
solar flares is highly dependent on the structure and topology of solar magnetic
fields. A new method for predicting large (M- and X-class) flares is presented,
which uses machine learning methods applied to the Zernike moments (ZM)
of magnetograms observed by the Helioseismic and Magnetic Imager on board
the Solar Dynamics Observatory for a period of six years from 2010 June 2 to2016 August 1. Magnetic field images consisting of the radial component of themagnetic field are converted to finite sets of ZMs and fed to the support vector
machine classifier. ZMs have the capability to elicit unique features from any
2D image, which may allow more accurate classification. The results indicate
whether an arbitrary active region has the potential to produce at least one
large flare. We show that the majority of large flares can be predicted within
48 hr before their occurrence, with only 10 false negatives out of 385 flaring
active region magnetograms and 21 false positives out of 179 non-flaring active
region magnetograms. Our method may provide a useful tool for the predictionof solar flares, which can be employed alongside other forecasting methods.

137

APSPM 2017
Session 3: Flare, ejection and space weather

Solar particle event statistical model comparison for
Korean Pathfinder Lunar Orbiter mission
Abstract Author(s): Dongmin Ryu, Insoo Jun, Sung-Joon Ye
Institution(s): Seoul National University, Jet Propulsion Laboratory/NASA
Presentation: P3 081
Abstract
South Korea is now conducting project for the Korea Pathfinder Lunar Orbiter(KPLO). For the successful mission with no failure caused by radiation, radiation environment analysis should be done properly. Radiation environment isdivided into three categories which are solar proton environment, trapped particle environment, and galactic cosmic radiation environment. Among them,solar proton environment is the main concern for the near-Earth interplanetary
mission because of its high energy and flux. For the detailed analysis of solar
proton environment, I compared several solar particle event statistical models and calculated total mission fluence for each model. JPL, ESP-PSYCHIC,
Rosenqvist, and King model were compared and analyzed. Geant4, a radiationtransport Monte Carlo simulation code, was used to estimate the eﬀect of solar
proton fluence to the spacecraft. From the fluence spectrum data, total ionizing
dose (TID) and displacement damage dose (DDD) were separately calculated.
Also, primary particle dose and secondary particle dose were calculated for thefurther analysis. As a brief result, 0.1 MeV integral fluence was 3.46E11 particles per square centimeter and total ionizing dose was about 80 Gray with 1
mmAl shielding for the case of JPL model. Through this work, we would be
able to optimize the radiation shielding design of spacecraft for the near-Earthinterplanetary mission.

138

APSPM 2017
Session 3: Flare, ejection and space weather

The Observation of Heart-shape Active Region 2529
Producing Strong M6.7 class Solar Flare and GradualCoronal Mass Ejections on 18th of April 2016
Abstract Author(s): Zety Sharizat bt Hamidi
Institution(s): Universiti Teknologi MARA
Presentation: P3 093
Abstract
During large event pre-flare usually continues a few minutes and followed by
impulsive phase about 3 to 10 minutes. In this study, the data of active regionof the Sun was taken from oﬃcial website of the Langkawi National Observatory.
The image of the active region was observed by using 11-inch Celestron telescopewith solar filter. This data confirms that there was a strong M class of solar
flare during the day due to eruption of AR 2529 was occurred on 18th of April
2016. The evolution of small AR 2529 to a big heart-shape forms an eruptionthat producing strong M6.7 class of flare and three gradual CMEs. This strong
flare caused significant impact around the high technologies of Pacific Ocean byfading the signal at frequencies below 15MHz. Active region 2529 also producing
three associated CMEs which each of them were distinguished by number insequence. AR2529 has developed a ’beta-gamma’ magnetic field that harbours
plenty of energy for this kind of explosion. CME number 46 is the fastest among
all CMEs during the day with the average velocity of 544 km s−1 . All of the
CMEs were classified as gradual CMEs.

139

APSPM 2017

Session 4
Solar interior and activity cycle of the Sun and stars

140

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Solar neutrino measurements at Super-Kamiokand
Abstract Author(s): Yasuo Takeuchi
Institution(s): Kobe University
Presentation: O4 020K
Abstract
Super-Kamiokande (SK) is a large water Cherenkov detector to study elementary particle physics and astroparticle physics. It is located in Kamioka Observatory, ICRR, The University of Tokyo. The detector consists from a cylindricalstainless steel tank (39.3 m diameter x 41.4 m height), 50 kton of purified water,
and about 11,100 of 20-inch photomultiplier tubes (PMTs). It is located 1,000m underground at Ikeno-yama Mountain, Kamioka town, Gifu, Japan.
SK started its observation in April 1996. Currently, 4th phase of the experiment is running. The main physics targets of SK are search for nucleon decay,
astrophysical neutrino measurements, and accelerator neutrino measurements.
The sun is most intense neutrino source on the surface of the earth. Solar neutrinos are one of major observation targets at SK. They are produced in thesolar core region with the nuclear fusion processes from four hydrogen nuclei
into a helium-4 nucleus. The measurements of solar neutrinos were started in
1970s.
In this presentation, a brief history of solar neutrino measurements, problem,and oscillation is explained. Then, solar neutrino measurements at SK are
reviewed. Finally, some solar astrophysics related topics in current SK and in a
future project, Hyper-Kamiokande, are mentioned.

141

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Recent development of solar dynamo model
Abstract Author(s): Hideyuki Hotta
Institution(s): Chiba University
Presentation: O4 021I
Abstract
Recent development of the solar convection and the dynamo model are reviewed.
The solar convection zone (the outer 30% of the solar interior) is fulfilled withturbulence of ionized plasma. This turbulence interacts with ubiquitous magnetic field. Then large-scale features such as 11-year cycle, are maintained. Inorder to understand generation process of the magnetic field using numericalcalculation, huge numerical resources are required for resolving small-scale turbulence and magnetic field. Recently new method, the Reduced Speed of Sound
Technique, and massive super computers, like K-computer enable us to carry out
such high-resolution calculations, which resolve turbulent inertia scale. Using
these high-resolution calculations, we found that the significant role of smallscale magnetic field on the large-scale magnetic field. In the high-resolution
calculations, small-scale dynamo becomes eﬃcient and the small-scale turbulence is significantly suppressed. As a result, the large-scale magnetic field isreproduced even in high-resolution situation. In the talk, the future path to thephotosphere in the global convection simulation is shown.

142

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Flux transport dynamo and solar cycle
Abstract Author(s): Jie Jiang
Institution(s): Beihang University
Presentation: O4 044K
Abstract
Flux Transport Dynamo (FTD) models usually refer to the models in which
meridional circulation plays a crucial role and the poloidal field generation takes
place by the Babcock-Leighton (BL) mechanism. The models were regarded as
the most promising one to understand the solar cycle. During the past few years,
the major developments relevant to FTDs are as follows. (1). The importantroles of the magnetic pumping, one of flux transport mechanisms, are recognized.
(2). The possible poleward meridional circulation at the base of the convective
zone given by helioseimology and MHD simulations brings a possible challenge
to FTD. (3) BL mechanism was confirmed to be at the heart of the solar cycle.
The significance of the BL mechanism for the solar cycle is twofold. One is thatthe long-term observational data over solar surface can be used to constrain theinterior dynamics. The other is that the observable part of the BL mechanism
makes the physics-based solar cycle prediction feasible. The possible strengthof the subsequent cycle can be predicted when a cycle starts for a few years.
(4). Some 3D kinematic BL type dynamo models have been developed.

143

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

A theoretical model of the variation of the meridional
circulation with the solar cycle
Abstract Author(s): Gopal Hazra, Arnab Rai Choudhuri
Institution(s): Indian Institute of Science
Presentation: O4 045
Abstract
Observations of the meridional circulation of the Sun, which plays a key role in
the operation of the solar dynamo, indicate that its speed varies with the solar
cycle, becoming faster during the solar minima and slower during the solar maxima. To explain this variation of the meridional circulation with the solar cycle,
we construct a theoretical model by coupling the equation of the meridional circulation with the equations of the flux transport dynamo model. We consider
the back reaction due to the Lorentz force of the dynamo-generated magnetic
fields and study the perturbations produced in the meridional circulation due
to it. This enables us to model the variations of the meridional circulation
without developing a full theory of the meridional circulation itself. We obtain
results which reproduce the observational data of solar cycle variations of themeridional circulation reasonably well. We get the best results on assuming themagnetic Prandtl number to be close to unity. We have to assume an appropriate bottom boundary condition to ensure that the Lorentz force cannot drive aflow in the subadiabatic layers below the bottom of the tachocline. Our results
are ensitive to this bottom boundary condition.

144

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Probing magnetic fields in the solar convection zone withsolar-cycle variations of meridional flows
Abstract Author(s): Chia-Hsien Lin, Dean-Yi Chou
Institution(s): National Central University, National Tsing-Hua University
Presentation: O4 046
Abstract
The solar meridional flow is a global flow that flows in the longitudinal direction.
It has been proposed to be an important driver for the solar-cycle variation andre-distribution of the solar magnetic flux. On the surface, it is typically observed
to flow from the equator toward the polar regions at a speed of approximately
1 km/s. Below the surface, however, the flow cannot be directly measured.
Despite the eﬀorts from many studies to probe the subsurface meridional flow,
there is still no consensus on the magnitude and profile of the flow field. Lian
& Chou 2015 applied a helioseismic time-distance method probe the solar cycle
variation of the subsurface meridional flow. The principle is to measure thetravel-time diﬀerence between a wave propagating in the opposite direction in a
meridional plane. The time diﬀerence reflects the direction and magnitude of theflow along the path of the wave. The travel distance between the two surface footpoints of the wave is related to the depth the wave can travel. By measuring thetravel-time diﬀerences of the waves with diﬀerent travel distances at diﬀerent
latitudes over a solar cycle, Lian & Chou 2015 created travel-time diﬀerence
maps as a function of latitude and time, and found significant diﬀerence at thebase of convection zone between the solar maximum and minimum periods. In
this present work, we use the travel-time diﬀerence data from Lian & Chou 2015,
and apply a helioseismic inversion procedure to infer the internal meridional flow
pattern. The objective is to probe the diﬀerence of the flow between the solar
maximum and minimum.

145

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Formation of dynamo-driven bipolar magnetic spots instratified turbulence
Abstract Author(s): Sarah JabbariInstitution(s): Monash University
Presentation: O4 047
Abstract
Recent direct numerical simulations (DNS) of large-scale turbulent dynamos instrongly stratified layers have resulted in surprisingly sharp bipolar structures atthe surface in both plane-parallel and spherical geometries. Here we present new
DNS of helically and non-helically forced turbulence with and without rotationin both Cartesian and spherical coordinates and compare with corresponding
mean-field simulations (MFS) to show that these structures are a generic outcome of a broader class of dynamos in density stratified layers. In all thesesimulations, the structures have a long life which we suggest to be due to theoccurrence of reconnection-like phenomena at the boarder between the opposite
polarities. In the box simulations, we focus on the formation of a current sheet
between bipolar regions and determine the reconnection rate. We demonstratethat for large Lundquist numbers, the reconnection rate is nearly independentof S. In the spherical geometry simulations, the kinetic helicity and therefore
also the large-scale magnetic field are strongest at low latitudes. For moderately strong stratification, several bipolar spots form that eventually fill the fulllongitudinal extent. At early times, the polarity of spots reflects the orientation of the underlying azimuthal field, as expected from Parkers -shaped flux
loops. At late times their tilt changes such that there is a radial field of opposite orientation at diﬀerent latitudes separated by about 10. We confirm thatin this model, strong stratification is essential ingredients behind magnetic spot
formation, which appears to be associated with downflows at larger depths.

146

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Studying Solar Interior and Higher Atmosphere using
Helioseismic Waves
Abstract Author(s): Dean-Yi Chou
Institution(s): National Tsing Hua University
Presentation: O4 049I
Abstract
The acoustic wave is a tool to probe the subsurface structure of sunspots. Theinteraction of solar acoustic waves with sunspots can be considered as a scattering problem. The scattering matrix is the most commonly used quantity todescribe the interaction of a scattering problem. Here we first discuss the measurements of scattered waves with helioseismic data, and then discuss how todetermine the scattering matrix elements from the measured scattered waves.
We also discuss the computation of the Green tensor, which relates the scattering matrix elements and the interaction term in the wave equation.

147

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Studying Solar Interior and Higher Atmosphere using
Helioseismic Waves
Abstract Author(s): Junwei Zhao, Ruizhu Chen
Institution(s): Stanford University
Presentation: O4 050I
Abstract
In this talk, we review recent progresses in helioseismology on three topics: solar meridional circulation, mapping and calibrating far-side active regions, andconnections between helioseismic waves and waves in the higher atmosphere.
Since the discovery of a systematic center-to-limb eﬀect in helioseismic measurements, many authors have measured meridional circulation and found theequatorward flow in the middle of the convection zone. However, their results
are not fully consistent. We will review these results and also present a new
eﬀort that measures the Sun’s meridional flow in a more comprehensive way,
which reveals a three-layer flow structure in the convection zone. For mapping
far-side active regions, previous codes used the waves that experience 4- and5-bounces traveling from the near side passing the far side and back to the nearside again. Now we further develop the code to include 3-, 6-, and 8-skip waves.
This greatly enhances the reliability of the acoustic images of the far-side active
regions, which are then calibrated using STEREO-observed far-side coronal images. To study the connections between helioseismic waves and waves observedin the chromosphere, transition region, and corona, we collect observations ofdiﬀerent atmospheric levels, and trace how waves channel up from the photosphere to the corona. It is also found that waves of diﬀerent frequencies follow
diﬀerent paths traveling upward.

148

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

3D Kinematic Model of the Solar Flux Transport Dynamo
Abstract Author(s): Arnab Rai Choudhuri, Gopal Hazra, Mark Miesch
Institution(s): Indian Institute of Science, High Altitude Observatory
Presentation: O4 051
Abstract
Much of our understanding about the solar cycle has come from 2D kinematic
model of the flux transport dynamo in which the mean field dynamo equations
are solved in the r-theta plane. However, the crucial Babcock-Leighton process
involving the buoyant rise of a part of a toroidal flux tube to produce a tilted
bipolar sunspot pair and its subsequent dispersal to build up the poloidal field
is an inherently 3D process, treated rather crudely in 2D dynamo models. The
build-up of the poloidal field from tilted bipolar sunspots has been treated more
realistically by the surface flux transport models which are solved in theta andphi, but are restricted only to the solar surface. The next step is the constructionof 3D kinematic flux transport dynamo models, in which the flows measured byhelioseismology are incorporated as in 2D models, but the magnetic field istreated in 3D. Such models combine the best features of the 2D kinematic flux
transport dynamo model and the 2D surface flux transport model. Work in thisdirection began only recently (Yeates & Munoz-Jaramillo 2013, MNRAS, 436,
3366; Miesch & Dikpati 2014, ApJL, 785, L8). I shall especially discuss ourrecent work (Hazra, Choudhuri & Miesch 2017, ApJ 835, 39) which shows thatsome results from the 2D surface flux transport model regarding the build-upof the polar field have to be revised considerably when subsurface processes aretreated realistically.

149

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Variation of Solar Microwave Spectrum in Last Half
Century
Abstract Author(s): Masumi Shimojo, Kazumasa Iwai, Ayumi Asai, Satoshi
Nozawa, Tetsuhiro Minamidani, Masao Saito
Institution(s): National Astronomical Observatory of Japan , Nagoya University, Kyoto University, Ibaraki University
Presentation: P4 082
Abstract
The total solar fluxes at 1, 2, 3.75, and 9.4 GHz were observed continuously from1957 to 1994 at Toyokawa, and from 1994 until now at Nobeyama, Japan withthe current Nobeyama Radio Polarimeters. We examined the multi-frequency
and long-term datasets, and found that not only the microwave solar flux but
also its monthly standard deviation well indicates the long-term variation ofsolar activity. Furthermore, we found that the microwave spectra at the solar
minima of Cycle 20∼24 agree with each other. These results show that the average atmospheric structure above the upper chromosphere in the quiet sun has
not varied for half a century, and suggest that the energy input for atmosphericheating from the sub-photosphere to the corona has not changed in the quiet
sun despite significantly diﬀerent strengths of magnetic activities in the last fivesolar cycles.

150

APSPM 2017
Session 1: Progress on instrumentation and future plans

Overview of the new science results obtained from
Kodaikanal digitized data archive: white-light and Ca-K
Abstract Author(s): Sudip Mandal, Subhamoy Chatterjee, Dipankar Banerjee
Institution(s): Indian Space Research Organization
Presentation: P4 083
Abstract
The Kodaikanal Observatory in India, has been acquiring the full disc images of
the Sun in photographic plates/films, in three diﬀerent filters since early 1900.
Recently, these plates have been digitized in high-resolution fits formats. In
this talk, I will present a summary of the results obtained using this digitizeddata archive, specifically the white-light data and the Ca-K data. I will also
talk about how this data can be used by the wider solar community in order toextract the best science out of it.

151

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Search for periodic modulations of the solar neutrino flux
in Super-Kamiokande
Abstract Author(s): Makoto Hasegawa, for the Super-Kamiokande collaboration
Institution(s): Kobe University
Presentation: P4 084
Abstract
Since solar neutrinos are generated in the solar core, they serve as an accurate
probe of the internal structure and activity of the sun. Super-Kamiokande(SK) has the largest target mass( 22.5kton) and one of the longest observation
periods ( 20 years) of MeV solar neutrinos. We have reported possible periodic
modulation of solar neutrino flux using the data taken between May 31st 1996
and Jul. 15th 2001(Phase SK-I ) in the frequency range from 0.00020/day to
0.09870/day. In that study, the maximum peak, consistent with no modulation,
was found at 0.1197/day (Phys. Rev. D 68 (2003) 092002) On the other hand,
it was pointed out that a maximum peak, consistent with modulation, is foundat around 9.43/year from several researchers by using the same data in SKI with diﬀerent analysis technique(e.g. Astroparticle Physics 82 (2016) 86-92). Therefore, we are trying to reanalyze SK-I data with an improved method(Generalized Lomb-Scargle method). The same method is also applied to SKIV data (between Oct. 6th 2008 and Jan. 31st 2014). In this presentation,
the current status and preliminary results of the improved periodic modulation
searches in Super - Kamiokande will be reported.

152

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Development of data-archives of solar chromosphericfull-disk images and researches on long-term variations ofsolar activities and the earths upper atmosphere
Abstract Author(s): Satoru UeNo, R. Kitai, A. Asai, T. Sakaue, T. Kawate,
S. Notsu, Y. Notsu, H. Watanabe, A. Shinbori, T. Shibayama
Institution(s): Kyoto University, Nagoya University
Presentation: P4 085
Abstract
Kyoto University has accumulated solar chromospheric full-disk images at Kwasan
Observatory, Ikomayama Solar Observatory, Hida Observatory and National Ica
University in Peru, since around 1929. In this poster, at first we introduce thedevelopment of a database of digitized images of CaII K full-disk analogue datathat were recorded on photo-plates or photo-films by using a spectroheliographmade by Askania company from 1929 to 1969. Next, we report the present results of our studies on long-term variations of solar activities and earths upper
atmosphere using this database and another database of H-alpha full-disk digital images taken by the Flare Monitoring Telescope (FMT) since 1992 at Hida
Observatory and Ica University. For example, we show the relationship between
geomagnetic solar daily quiet variation (Sq), solar radio flux F10.7 and plage
index that stands for the total area of plage regions on CaII K full-disk images
from 1945 to 1965, and diﬀerences between the minimum phase of Solar Cycle
22/23 and the minimum phase of 23/24 whose activity was especially low.

153

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Waiting time distributions of solar and stellar activities:
Poisson process or with memory?
Abstract Author(s): Chuan Li, Sijia Zhong, Zigong Xu
Institution(s): Nanjing University, Southeast University
Presentation: P4 086
Abstract
The statistics of time interval between two successive events provide information
whether solar and stellar activities occur independently or with memory? Here
we examine the waiting time distributions (WTDs) of solar flares and coronalmass ejections (CMEs), as well as the stellar flares observed by the Kepler mission. Based on the Kolmogorov-SmirnovK-Stest, we make a quantity analysisof the departure of WTDs from the Poisson process as predicted by the selforganized criticality (SOC) theory. We then fit the WTDs with three functions:the non-stationary Poisson distribution (Wheatland 2000; Li et al. 2014), theLevy function (Lepreti et al. 2001), and the Weibull function (Weibull 1951;
Telloni et al. 2014). It is found that a certain amount of memory is characterized during periods of high solar activities, while the random Poisson process
dominates during solar minimum.

154

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Shock Merging in the Chromosphere of Sunspots
Abstract Author(s): Kyeore Lee, Jongchul Chae
Institution(s): Seoul National University
Presentation: P4 087
Abstract
Our H observation of Fast Imaging Solar Spectrograph installed at the Goode
Solar Telescope in Big Bear Solar Observatory shows that merging of shockwaves in sunspots of the solar chromosphere occurred frequently. We madetime-Doppler velocity map from H data to statistically analyze the shock merging phenomena. One of sunspots has 197 shock merging features during 84minof stable observation. Shock merging distributed at whole part of the sunspot
and slightly concentrated on the boundary between umbra and penumbra. It
is considered that one faster shock front catch up with a shock front ahead,
therefore merging region can be not only one spot but also a front. We anticipated decrease of wave front by shock merging means increase of wave period,and verified it using wavelet method. It shows that a series of shock merging
can double the wave period at edge of the sunspot region compared with centerof the sunspot. Earlier studies using acoustic cutoﬀ frequency theory explained
well the wave frequency gap between 3min in umbra and 5min in penumbra withsome assumptions, however, shock merging can account for both frequency gap
and nonlinear features concisely.

155

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Data Processing for Multiple Solar Activity Cycles
Abstract Author(s): Ganghua Lin, Suo Liu, Xiaofan Wan, Xiao Yang, Xiangyun Zeng, Mei Zhang, Haimin Wang, Xun Yan
Institution(s): National Astronomical Observatories of China, Big Bear Solar
Observatory
Presentation: P4 088
Abstract
We are proceeding the data processing for multiple solar activity cycles. Theseobservation data were recorded in diﬀerent times and are from more then 7 observatories in the world. The work final purposes in science are by combining a
century solar Halphae data in the world, we look forward to study the statistical properties of solar filaments in multiple solar cycles, and thereby understandthe unusual behavior of solar cycle 24, the global structures of solar eruptions,
Moreton waves and sympathetic eruptions. The realization of scientific purposes
are mainly rely on some incredible progresses on multi-parameters calibration
method of Halpha data, automatic detection of solar activity features, and soon. In the presentation, we will show our some results in the project, for examples, automatic extraction of time stamp, standardized processing, flat field,
automatic solar activity features extraction,etc.

156

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Influence of strong viscosity on convective energy
transport
Abstract Author(s): Shota Arai, Hideyuki Hotta
Institution(s): Chiba University
Presentation: P4 089
Abstract
Many studies have suggested that current solar convection simulations would
overestimate the convective velocity. This problem comes from lack of ourunderstanding of the deep solar convection. Recent high-resolution magnetoconvection simulations suggest that small-scale magnetic fields enhance eﬀective
viscosity and suppress convective velocity. Furthermore, this enhancement isstronger in the higher resolution and not numerically converged. This implies
that eﬀective viscosity would be significantly strong in the real Sun. This finding
could contribute to the problem mentioned above. Inspired by this, we carryout a series of thermal convection simulations to investigate the influence of highviscosity on the convective energy transport by increasing kinematic viscosity.
The convective velocity in the strongest viscous case is about 10% of that in
the weakest viscous one at the bottom boundary. Instead of the significant reduction of the convective velocity, the decrease of the convective energy flux isrelatively small. We attribute this to the changes of the structure of thermal
fluctuation, leading to eﬃcient convective energy transport. In this talk, we
discuss how the structure of thermal fluctuation changes and the application of
our results to the thermal convection with the strong magnetic field in the real
Sun.

157

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Studies on the acoustic directionality of solar
flare-induced quakes
Abstract Author(s): Alina Donea
Institution(s): Monash University
Presentation: P4 090
Abstract
Magnetic and non-magnetic photospheric simulations of seismic ripples generated by solar flares are presented. We have considered various spatial andtemporal distributions of multiple seismic sources, by trying to imitate the observed solar quakes. As a result, the simulations reveal that the response of thephotosphere to all flare perturbations present ”acoustic directionality characteristics” that lead to a high degree of wave anisotropy. I will present the mostconclusive cases of our analysis, which provide answers to some of the unsolved
clues related to solar quakes and their not so ubiquitous existence.

158

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Merging Mosaics and Super-Mosaics of High Resolution
Vector Magnetic Field Maps for Studies of Spatial
Spectra of Solar Magnetic Field and Helicity
Abstract Author(s): K. Kuzanyan, K. Otsuji, T. Sakurai, N. Yokoi
Institution(s): IZMIRAN, Kyoto University, National Astronomical Observatory of Japan , The University of Tokyo
Presentation: P4 091
Abstract
Knowledge of spatial spectra of magnetic and velocity fields and their helicities (correlation of the field and its curl) in turbulent media are very importantfor understanding the underlying physics. In observations, likewise in numerical simulations, the significant restriction of revealing these quantities fromavailable data is the limit of scale separation between the smallest resolved (orpixelized) scale and the largest scale of the available field of view. The vector
magnetic field data obtained from SOT SP on-board Hinode provide high resolution maps with limited field of view. For practical studies, the field of view
can be eﬀectively increased up to the limits of the curvature of the solar surface(for application of models without account of projection). We proposed theprocedure of matching the normal mode and fast mode high resolution mapsof vector magnetic field for computation of larger field of view maps of magnetic energy and current helicity. A series of mosaic (matching two subsequentmaps) and super-mosaic (matching a series of maps in vertical and horizontal
dimensions) have been proposed for Hinode SOT observational program. The
first results of analysis of the merged maps show interesting properties of the
turbulence that occur near the edge of the resolution but still reliably resolved
scales of order of solar granulation. These imply a possibility of the eﬀect ofbottle-neck in transport of energy and helicity across the scales of this range.

159

APSPM 2017
Session 4: Solar interior and activity cycle of the Sun and stars

Construction of a mean field model of the convection zone
with turbulence transport coeﬃcients parameterization
based on 3D global simulations
Abstract Author(s): Ryuji Mineta, Hideyuki Hotta, Takaaki Yokoyama
Institution(s): The University of Tokyo, Chiba University
Presentation: P4 092
Abstract
In the solar turbulent convection zone, large-scale mean flows are observed.
One of them is the diﬀerential rotation. The momentum and heat transportsby small-scale turbulence are believed to be important processes to drive thislarge-scale flow. 2D axisymmetric mean field models, in which the turbulent
transports are parameterized, have been used in order to reveal the origin of
this large-scale flow. On the other hand, recent 3D global simulations can resolve the small-scale flow. However, the results of the 3D simulations are socomplicated that it is diﬃcult for us to investigate the important processes
driving the large-scale flow obtained in the 3D simulation. In order to overcome
this diﬃculty, we calculated the angular momentum using the simple axisymmetric model with the turbulent transport which is obtained from the analysisof the 3D global simulation. Through this new parameterization, 2D mean-fieldmodel itself should be improved by introducing more sophisticated turbulent
transport eﬀects. For the first step, we compared the result of the axisymmetricmodel with that of the 3D simulation to confirm that the turbulent transport
is correctly included in the axisymmetric model.

160