高エネルギー現象で探る宇宙の多様性Ⅰ
2021 October 18(Mon)-19(Tue)
Institute for Cosmic Ray Research, the University of Tokyo (Kashiwa/On-line)

磁気再結合における粒子加速の理解を目指して：
太陽フレア観測衛星 PhoENiX計画
Physics of Energetic and Non-thermal plasmas in
the X (= magnetic reconnection) region
Noriyuki Narukage (NAOJ)
Mitsuo Oka, Yasushi Fukazawa, Keiichi Matsuzaki, Shin Watanabe,
Taro Sakao, Kouichi Hagino, Ikuyuki Mitsuishi, Tsunefumi Mizuno,
Iku Shinohara, Masumi Shimojo, Shinsuke Takasao, Tomoko Kawate,
Takafumi Kaneko, Seiji Zenitani, Hiroshi Tanabe, Munetaka Ueno,
Tadayuki Takahashi, Takeshi Takashima, Masayuki Ohta andPhoENiX WG member

1Science Goal
Understanding of particle acceleration during magnetic reconnection• Science Objectives
1. To identify
particle acceleration sites
in reconnection-associated structures insolar flares
2. To investigate
the timing of particle acceleration
during reconnection-associatedphenomena in solar flares
3. To characterize
the properties of accelerated particle
populations in solar flares

2Particle acceleration
Accelerated particles are deviated from equilibrium.

Thermal equilibrium= Maxwell distribution
Number of electrons

Accelerated particle＝ power-law spectrum

1 keV

10 keV 100 keVEnergy of electrons

1 MeV

3

Particle acceleration
The energy of accelerated particles achieves up to 1020 eV.
Accelerated particles are ubiquitously detected in the universe.

××

Makishima (1999)

4

Particle acceleration
How are particles accelerated? It is not fully understood.

Super Nova Remnant(long time acceleration)

Gamma-ray Burst(short time acceleration)

SN 1006

Gamma rays

Credits: eCUIP and ISDC

Balbo+ 2011

1st order Fermi-acceleration
Statistical acceleration

How are particles accelerated
in very short time?
5Particle acceleration
Magnetic reconnection is a key.
Figure 1. from Reconnection-powered Linear Accelerator and Gamma-Ray Flares in the Crab Nebula
Uzdensky, Cerutti, & Begelman 2011 ApJL 737 L40 doi:10.1088/2041-8205/737/2/L40
http://dx.doi.org/10.1088/2041-8205/737/2/L40© 2011. The American Astronomical Society. All rights reserved.

alubeN barC eht ni seralF yaR-ammaG dna rotareleccA raeniL derewop-noitcennoceR morf .3 erugiF
04L/2/737/5028-1402/8801.01:iod 04L 737 LJpA 1102 namlegeB & ,ittureC ,yksnedzU
04L/2/737/5028-1402/8801.01/gro.iod.xd//:ptth.devreser sthgir llA .yteicoS lacimonortsA naciremA ehT .1102 ©

Gamma-ray Burst(short time acceleration)

Uzdensky+ 2011
Magnetic reconnection
Ma

gn
etic

ene

rgy

è

è

Kin
Th etic
erm enal e ergy
nergy
Gamma rays

Credits: eCUIP and ISDC

Balbo+ 2011

How are particles accelerated
in very short time?
6Magnetic Reconnection
MR is fundamental plasma process and ubiquitously occurs in the universe.

Lundquist number𝑆≡

𝜇! 𝑉" 𝐿#$𝜂

Cf. Reynolds number

Re = 104

Ji & Daughton 2011

Re = 1.54

Effective
plasma size

𝜆≡

𝐿
𝑑%

7

Significance of solar flare study[Plasma physics]
Natural laboratory of plasma• Magnetic reconnection• Particle acceleration[Unique observation target]
The closest star•

Solar phenomenon can beobserved with wide field of view andwith spatial and temporal resolutions[Impacts on the Earth and social environments]
The mother of the Earth• Evolution of life (cosmic rays)• Space weather[As a star]• Reference of other astrophysical objects

8Magnetic Reconnection Picture in Solar Flarehas been established by both observation and theory.

Observation

Model

SDO Spots X8.2-Class Solar Flare,Sep 10, 20179

Magnetic Reconnection Picture in Solar Flarehas been established by both observation and theory.

Observation

Model

10

Aschwanden et al. (2017)

Magnetic reconnection & Particle acceleration
in solar flare
1. A solar flare is an efficient accelerator.
Aschwanden et al. (2017)
Ion
acc.

Magnetic
EnergyMagnetic
reconnection

Kinetic
Energy(Bulk motion)

CME
Directheating

Electronacceleration

ThermalEnergyParticle
Acceleration
Non-thermal
Energy

FACT: > 50 % of energy
released by MR is spentfor particle acceleration

Accelerated
Particles

2. The particle acceleration isa key to energy release andconversion in solar flares.
11

pl
sh
as
oc
m
k
oi
d

cu
sh rre
ee nt
t
ou
tf
lo
w

Magnetic reconnection & Particle acceleration
in solar flare

Magnetic
reconnection

Magnetosphericand Ionosphericdisturbance

Plasma cloudInterplanetary
space
Magnetic
EnergySpace
Weather

CME, Jet

Shock

Downflow

Termination
shock

Solar surface

Kinetic
Energy(Bulk motion)

Non-thermal
EnergyRadiation
EnergyCoronalHeating

Plasmoid

Shock Acc.?

Multiple X-line?
ThermalEnergyAccelerated
Particles

Thermal pool

Statistical Acc.?
Single X-line?
FACT: > 50 % of energy
released by MR is spentfor particle acceleration

Particle
Acceleration

Non-thermal
EnergyTrapping inloop

Accelerated
Particles

Chromosphericevaporation &condensation

Flaring loop,
etc.

ThermalEnergy12

Particle Acceleration is one of
the long-standing major puzzles in solar physics
By hard X–ray observations, it is known that theparticles are accelerated by solar flares.
But even particle acceleration site is still puzzle.

[Reason 1] Poor observations, especially forthe energy release region (around the X-point)
DC acceleration?

?

Collapsing magnetic traps?

Shocks?

?

Turbulence?

Aschwanden (2002)

Karlicky & Kosugi (2004)

Tsuneta & Naito (1998)
Takasao & Shibata (2016)

Liu et al. (2008),
Petrosian, (2012)

Accelerator
Accelerated
Particles?

MHD scale~ 107 - 1010 cm (Size of plasma structures)?

~ 10 sec (Alfven time)[Reason 2] Huge scale gap in both space and time!!
Particle scale~ 100 - 102 cm (Electron - Ion Larmor radius)<< 1 sec13

Non-thermal component around X-point
Narukage et al. (2014) ApJ, 787, 125

New observational
approach

Focusing Imaging-Spectroscopy
in soft and hard X-rays
Spectro-Polarimetry
in soft Gamma-rays

x, t, E, pol

Numerical
approach
MHD+GCA
PIC
Emission model

La

Sp
bo

ra

So
to

la

ry

r

ac

Ph

A
e

ys

Ph

ic

st

ys

ro

ic

s

ph

ys

ic

s

Interdisciplinary
approachsParticle Acceleration
Magnetic Reconnection

Science Objectives of PhoENiX mission
1. Identify particle acceleration sites
in solar flares [where]
2. Investigate temporal evolution ofparticle acceleration [when]
3. Characterize properties ofaccelerated particles [how]planned to be realizedin Solar Cycle 26 (2030’)
15

Why X-rays and Gamma-rays?
– comparison with spectroscopy in other wavelengths
Significant

New by PhoENiX

Collaboration

Wavelength

EUV

Soft X-rays

Hard X-rays

Gamma-rays

Radio

Energy< 0.1 keV

0.1 – 10 keV

10 – 100 keV

0.1 – 1 MeV

0.1 – 1 MeV

Common properties
Dynamic range

✅✅

✅✅✅

✅✅✅

✔

Field of view

✅✅

✅✅✅

✅✅✅

✅✅✅

Spatial sampling

✅✅✅

✅✅

✅✅

✔

Temporal sampling

✅✅

✅✅✅

✅✅✅

✅✅✅

✅✅✅

For investigation of thermal plasmas (possible agents of particle acceleration)
Temperature diagnostic capability

✅✅✅

✅✅✅

✅✅

Response speed to temperature change

✔

✅✅✅

✅✅✅

Velocity measurement of bulk plasma

✅✅✅

✅✅

✅✅

✔

For investigation of non-thermal plasmas (particle acceleration)
Accelerating electrons

(✔ )

✅✅✅

✔

Accelerated electrons

(✔ )

✔

✅✅✅

✅✅

✔

Low energy cutoff✅✅✅

Maximum energy✅✅

Electron anisotropy

✅✅

✅✅✅

✔

Magnetic field measurement
Magnetic field measurement✔

16

Required measurements to trace the accelerated
particles in MHD-scale solar flare system(Update from past or existing observations)

ZONE

Propagationof accelerated
particles

X

Structural
Property in particle acceleration
characteristic
point of view

Observational
Observational capability
capability
Past or existing obs.

ZONE1

Aroundreconnection
site• Energy release region
è Possible acceleration site

Few samples
in X-ray obs.

ZONE2

Above-theloop-top• Boundary between rare anddense plasmas
è Possible acceleration site

Sometimes observed
as hard X-ray coronalsources

Flare loop

• Transit area
• Trapping areaè Possible acceleration site

Few samples
in hard X-ray obs.

ZONE3

ZONE4

Foot points ofthe flare loop
(Solar surface)• Energy deposition region• Mirroring region

Requirements for new
obs.
Plasma diagnostic
capability
for both thermal andnon-thermal plasmas
in inallalltheZONE
ZONEs

and capability to tracktrace
the propagation of
Observed in manyflares as the brightest accelerated particles
hard X-ray source

ZONE2

17
ZONE4

ZONE4

Observational Approach for Scientific Objectives
Spatially resolved
spectrum in X-rays
Thermalcomponent

Temperature

Non-thermal
component

Temporal evolution of spectrum

Energy transportation & budget• Released magnetic energy= EB_pre-flare – EB_post-flare

Ion
acc.
CME
Directheating

Electronacceleration(accelerated electrons)?

EM (Density) Spectrum Index• Kinetic energy of bulk plasma = 1/2 Np mp v2• Thermal energy = ∫ 3/2 N kB T dT
• Energy of accelerated particles = ∫ NNT ENT dE18

Capability

PhoENiX

Other (past or existing) X-ray missions
In the case of
short exposure,the dark region
cannot beobserved.

Dynamic Range

In the case oflong exposure,the blooming
happens andcontaminates
the dark
region.

Aliasing
pattern

To observe entire
ZONEs[SXR & HXR]
Focusing optics (mirror)+ CMOS or CdTe

Imaging Spectroscopy
SXR:• Thermal plasma• Accelerating e• Low energy cutoff
HXR:• Accelerated e-

3 MK

18 MK
Super-hot
30 MK
Non-thermal[SXR]
Focusing optics (mirror)+ CCD
No
Spectroscopic
Data

Super-hot
30 MK
Non-thermal

Energy [kev]Energy [kev][SXR & HXR]
Imaging spectroscopy[HXR]
with modulation
collimator[SXR]
Mainly Imaging only

[HXR]
Imaging spectroscopy
19Capability

PhoENiX

Other (past or existing) X-ray missions
Polarization = 6 ± 25%
for 100 – 350 keV in M7 flare

Minimum detectable
polarization degree< 10%

Polarization• Electron anisotropyç Expected modulation
polarization with PhoENiX for
60 – 300 keV in an M3.4 flare.
Assumed polarization degree
is 20%.

(velocity angle to theguiding magnetic field)• High energy cutoff(highest energy
electrons produced by
the acceleration
conditions: mechanism,spatial extent, andtime)

Suarez-Garcia et al. (2006)

There are some studies to estimate
the polarization in solar flares withRHESSI. But RHESSI is not designed(calibrated) to derive the polarization.
CHAPTER 14. GAMMA-RAYS

608

Jeffrey et al. (2020)
1010
Nonthermal
electrons

High-energetic High-energetic
ionselectrons

105

e+

10-5

+ Imaging+ Pol.

SOFT X-RAYS

HARD X-RAYSn

2.2 MeV

100

10

Pions

We plan to upgrade

511 keV

Energy Coverage

Flux (photons cm-2 s-1 keV-1)

Thermalelectrons

π
GAMMA-RAYS

-10

100

101

102

103
Photon energy [keV]

104

105

106

Figure 14.1: Composite photon spectrum of a large flare, extending from soft X-rays (1 10keV), hard X-rays (10 keV 1 MeV), to gamma-rays (1 MeV 100 GeV). The energy spectrum
is dominated by different processes: by thermal electrons (in soft X-rays), bremsstrahlung from20

Specification of the PhoENiX instruments
観測能力

要求値

根拠

太陽フレアを観測するために必要な性能（全てのエネルギー帯域の観測に共通の要求）

視野
観測時間
時間分解能

> 360×360 arcsec2> 10 minutes

少なくとも、フレア発生前からフレアピークまでを観測できること< 10 sec per spectrum< 1 sec per lightcurve

スペクトルに対してはAlfvén時間で規定
ライトカーブに対しては加速電子の伝搬時間で規定

フレア領域全体が視野に収まること

太陽フレアシステムが生み出すプラズマ構造（加速源）と加速中の電子集団を調査するために必要な性能：軟X線集光撮像分光

エネルギー範囲

0.5 keV – 10 keV

プラズマ構造の温度（熱的スペクトル）と、加速中の電子の情報（熱的分布から乖離していくスペクトル）が取得できること

エネルギー分解能< 0.2 keV (FWHM)

物理情報を引き出すために、輝線群と連続光成分が分離可能なこと

空間分解能< 2 arcsec (FWHM)

磁気再結合が生み出す構造にはスケールフリーなものが含まれるため、次の様に設定する。大規模フレア（~105 km ~ 140”）では各ZONE内を分解し各プラズマ構造が識別できること。小規模なフレア（~104 km ~ 14”）では少なくともフレア領域をZONE1〜4に分離できること。

ダイナミックレンジ> 104

フレアループが増光しても、全てのZONEをくまなく観測できること> 1600 photons

温度・密度の測定誤差を10% 以下に収めること

スペクトル毎の光子数
エネルギー範囲加速された電子集団の検出と、その伝搬を追跡するために必要な性能：硬X線集光撮像分光
5 keV – 30 keV
加速電子の情報（熱的分布から乖離した冪型スペクトル）の取得のためエネルギー分解能< 1 keV (FWHM)

加速状態が異なる成分（冪型スペクトルの折れ曲り）も検出できること

光源位置の決定精度< 2 arcsec

空間分解能< 4 arcsec (FWHM)

空間分解したプラズマ構造（加速源候補）に対して、加速電子が存在する領域の位置を決定することが重要であり、その精度は、プラズマ構造の調査に必要な空間分解能と同じである必要がある。なお、この位置決定精度を達成するた
め、その2倍程度の空間分解能も必要である。

ダイナミックレンジ> 103

ループの足元が増光しても、全てのZONEをくまなく観測できること

スペクトル毎の光子数> 3200 photons

加速電子の総数の測定誤差をファクター2以下（50%〜200%）に収めること加速された電子の運動の非一様性と最高到達エネルギーを調査するために必要な性能：軟ガンマ線偏光分光

エネルギー範囲
エネルギー分解能

20 keV – 300 keV, 数MeV
< 10 % (FWHM)

より高いエネルギーにまで加速された電子の情報を取得するため加速状態が異なる成分（冪型スペクトルの折れ曲り）も検出できること

測定可能な偏光度の下限値< 10 % in >M5 class flares

加速電子の運動の非一様性を評価するため [6]。ただし測定手法に起因し、偏光測定のエネルギー範囲は60 keV – 300 keVになる。

スペクトル毎の光子数> 500 photons

上記の偏光測定精度を達成するため

21

Instruments and Key technologies of PhoENiX
The basic developments of these technologies have been completed.

Soft X-ray Imaging Spectrometer（0.5 keV ~ 10 keV）

Hard X-ray Imaging Spectrometer（5 keV ~ 30 keV）
反射鏡支持上面部

210 mm

反射鏡支持側面部

反射鏡
反射鏡支持下面部
図: 高精度反射鏡機構の試作品デザイン (左) と外観写真 (右)Soft Gamma-ray SpectroPolarimeter（20 keV ~ > 300 keV（> 1 MeV））~2.0m

High-speed soft X-ray camera
Back-illuminated CMOS sensor~3.0m

High-precision X-ray mirror
Resolution: < 2 arcsec
Low scatter: 10-4 @ 20 arcsec

Large effective area X-ray mirror
Resolution: < 4 arcsec (FWHM)

High-sensitivity hard X-ray camera
Fine-pitch CdTe detector

Si/CdTe Compton camera with active shield
Polarization measurement: > 60 keV

22

FOXSI sounding rocket seriesObs. target

TODAY– Demonstration of SXIS & HXIS of PhoENiX

FOXSI-1 in 2012FOXSI-2 in 2014

FOXSI-3 in 2018

FOXSI-4 in 2024

Quiet sun

Active region and
Quiet sunFull sunincluding Active region

Solar flareSoft X-rays
0.5〜10 keVEnergy range
Hard X-rays
5〜30 keV

Telescope

Detector

7 shells x 7 modules

Si (7.7 arcsec) x 7[for hard X-rays]

10 shells x 2 modules
7 shells x 5 modules(10 shells + blocker) x 1(7 shells + collimator) x 2 high resolution optics x 5
10 shells x 3 modules
10 shells x 2 modules
7 shells x 1 modules

CdTe (6.7 arcsec) x 2
Si (7.7 arcsec) x 5[for hard X-rays]

CdTe (6.7 arcsec) x 2
Si (7.7 arcsec) x 4[for hard X-rays]+
CMOS (1.1 arcsec) x 1[for soft X-rays]

CdTe (6.7 arcsec) x 5[for hard X-rays]+
CMOS (1.1 arcsec) x 2[for soft X-rays]

23

FOXSI-3 flight on 7 September 2018

本研究は、下記のJSPS科研費の助成を受けたものです。
• JP18H03724（基盤研究(A)、研究代表者：成影典之）• JP17H04832（若手研究(A)、研究代表者：石川真之介）• JP16H02170（基盤研究(A)、研究代表者：高橋忠幸）• JP16H03966（基盤研究(B)、研究代表者：渡辺伸）• JP15H03647（基盤研究(B)、研究代表者：成影典之）• JP24244021（基盤研究(A)、研究代表者：高橋忠幸）• JP21540251（基盤研究(C)、研究代表者：成影典之）• JP20244017（基盤研究(A)、研究代表者：高橋忠幸）

24

see colour scale) of two active regions taken with Hinode/XRT (sensitive toflaring activity during the time interval, and was selected for the analysis.
The GOES lightcurve is for the full Sun, and the XRT and FOXSI lightcurves
tion statistical errors. The gaps in the FOXSI-2 lightcurve show the intervals
image in a.

FOXSI-2 result was published from Nature Astronomy（Ishikawa et al. 2017）
launch of FOXSI (FOXSI-3), the Nuclear Spectroscopic Telescope
Array (NuSTAR) spacecraft16 and a potential future solar-dedicatedmission that is in the early stages of development.

Methods

Coronal DEMs are usually evaluated by EUV and SXR observations7,17,18. Because
intensities of the EUV lines sensitive to high temperatures (~10 MK and above; forexample, Fe xxiii and Fe xxiv lines with sensitivity peaks at 10–20 MK) are weakin the absence of large flares, only a few detections of those lines in quiescent active
regions have been reported. The few positive reports19 are based on multi-filter
SXR observations by the XRT, especially using the thick filters. However, the XRT
uncertainties are large in the temperature range of flare-heated plasma20, and so
the high-temperature components are poorly constrained without the additionaluse of bremsstrahlung HXRs. The primary solar HXR instrument is the RHESSI
spacecraft, which has never detected significant emission localized in individualquiescent active regions due to limited sensitivity. In the case of ref. 19, follow-on
work using RHESSI’s non-detection was used to significantly constrain the hot
plasma present12. In this case, RHESSI supplies only an upper limit, and the hot

7–9 keV

DEM (cm–5 K–1)

1022

b 10

Hinode1020
1018∝ T –12

FOXSI

1016

HXR (counts s–1 keV–1)

a

1

1014
2

3

5
10
20
Temperature (MK)

4

5

6
7 8
Energy (keV)

9 10

Fig. 2 | Estimated DEM and HXR spectrum of the quiescent active region.
a, Estimated DEM of the quiescent active region from FOXSI-2 andHinode/XRT observations, and loci curves for observed quantities.
2

25

FOXSI-3 Soft X-ray data
250 FPS data (4 ms continuous exposure)time profile

image (like pointillism)   

spectrum 
         

26

Data analysis softwareThis full sun image is drawn
by dotting about 10 million
individual X-ray photons.

Data analysis software (GUI tool) for FOXSI-3
1. Selection of area, timing and energy range
2. Adjustment of binning for space, time and energy
3. Spectral fitting with XSPECThis version is developed with
IDL, which is widely used insolar physics community.
27

FOXSI-4 sounding rocket project :It’s time to observe a flare!!
First sounding rocket to observe a solar flare
Science objectives:
1. Determine how much particle acceleration occurs in the gradual phase of a flare
2. Produce images and spectra of flare footpoints from thermal to non-thermalenergies

FOXSI-4

Hi-C Flare

3. Determine where non-thermal sources and heated plasma are located in a given
coronal configuration

FOXSI-4

4. Measure the spatial distribution of superhot sources in a flare
5. Identify locations of energetic electrons in an erupting CME

Hi-C Flare• Method: Focusing imaging spectroscopy in X-rays (update of
FOXSI-3 observation)

July, 2020
Proposal was

Schedule

accepted by
NASA

2021

2022

2023

2024

Design &Development

Fabrication &TestIntegration &Test

Launch!!
28

FOXSI-4 sounding rocket project
High-precision electroformed
X-ray mirror

Paraboloid

Goal (cf. FOXSI-3)• <10” HPD (ç 25” HPD)
• <4” FWHM (ç 5” FWHM)

Hyperboloid

200 mmWolter type I mandrel (left) and circumferential
errors (right)

Updated CMOS (for soft X-rays) &CdTe (for hard X-rays) detectors
CMOS detector (cf. FOXSI-3)
25 um depletion layer thickness (ç 4 um) for• Higher sensitivity to high-energy X-rays• Higher robustness against X-rays

反射鏡支持上面部

210 mm

反射鏡支持側面部

反射鏡

Photon counting
capability of
CMOS(with 55Fe source)

反射鏡支持下面部
図: 高精度反射鏡機構の試作品デザイン (左) と外観写真 (右)CdTe detector (cf. FOXSI-3)• Position resolution ( ~30 μm ç 60 um)• High Count Rate (~5 k events / s / detector
ç 500 events / s / detector )Sub-strip resolution(Furukawa et al., 2020)29

Development of key technologies– Soft X-ray mirror, Soft Gamma-ray spectropolarimeter
High precision soft X-ray glass-polishedmirrorSi/CdTe Compton camera with active
shieldDesign for PhoENiX: 1CC
PhoENiX/SXIS

Cf. PhoENiX/HXISBGO design as• Active shield for polarimetry• Detector to evaluate maximum
energy (for above MeV detection)< 2” FWHM< 4” FWHM(Hinode/XRT)(previous page)30

New observational
approach

Focusing Imaging-Spectroscopy
in soft and hard X-rays
Spectro-Polarimetry
in soft Gamma-rays

x, t, E, pol

Numerical
approach
MHD+GCA
PIC
Emission model

La

Sp
bo

ra

So
to

la

ry

r

ac

Ph

A
e

ys

Ph

ic

st

ys

ro

ic

s

ph

ys

ic

s

Interdisciplinary
approachsParticle Acceleration
Magnetic Reconnection

Science Objectives of PhoENiX mission
1. Identify particle acceleration sites
in solar flares [where]
2. Investigate temporal evolution ofparticle acceleration [when]
3. Characterize properties ofaccelerated particles [how]planned to be realizedin Solar Cycle 26 (2030’)
31

Numerical
Approachλ ~ 10 (Hoshino et al. 2001)

λ ~ 100 (Guo et al. 2015)
Model of
Shibata & Tanuma
2001

Lundquist number𝑆≡

𝜇! 𝑉" 𝐿#$𝜂

Cf. Reynolds number

Dynamical Petschek
S < 106(Shibayama et al. 2015)

Re = 104

b.
La

MHD

PIC

Plasmoid chain MR
104 < S < 106
Ji & Daughton 2011

Re = 1.54

Effective
plasma size

𝐿
𝜆≡
𝑑%

Sweet-Parker modelS < 10432

Strategy of numerical approach• MHD calculation (~ 107 - 1010 cm) + test particle• Determine global energy release process• Provide the magnetic field and velocity field structures(boundary conditions of particle calculations)• e.g., Shocks, Magnetic mirror• Particle calculation (~ 100 - 102 cm)• e.g., Scattering processes via the wave-particle interaction, etc.
àFor example, pick up local regions and study acceleration& trapping processes using kinetic models (e.g., PIC)
• Comparison between numerical simulation and observation• via emission model• Energy spectrum ⇔ Photon spectrum• Electron anisotropy ⇔ Polarization, etc.
33

Numerical Approach to combine micro andmacro scales for comparison with observations
Reconnection region

Propagationof accelerated
particlesX

See also
Shibata & Tanuma 2001,
Drake et al. 2006, Oka et al. 2010,
Shibayama et al. 2015,
S. Wang, Yokoyama, Isobe 2015,
Kowal et al. 2017,
Hoshino 2017

λ ~ 100 (Guo et al. 2015)

Huang & Bhattacharjee 2016

Above-the-loop-top region
See also
Takasao & Shibata 2016,
Shen et al. 2018

Kaneko & Takasao in prep.

X. Kong et al. 2019, 2020

Foot-point regions
Acceleration by Alfven waves:
Fletcher & Hudson 2007,
Reep et al. 201834

Numerical Approach to combine micro andmacro scales for comparison with observations
Reconnection region

Propagationof accelerated
particlesX

See also
Shibata & Tanuma 2001,
Drake et al. 2006, Oka et al. 2010,
Shibayama et al. 2015,
S. Wang, Yokoyama, Isobe 2015,
Kowal et al. 2017,
Hoshino 2017

λ ~ 100 (Guo et al. 2015)

Huang & Bhattacharjee 2016

Most previous studies focus on electron acceleration
processes in specificregion
regions in a solar flare system.
Above-the-loop-top
See also
However, it is highly possible that electrons experience
Takasao & Shibata 2016,
multiple accelerations, trapping, etc. at differentShen
locations.
et al. 2018

So we need a model to combine them within a single
Kaneko & Takasao
prep.
X. Kongunderstanding.
et al. 2019, 2020
framework
forincomprehensive
Foot-point regions
Acceleration by Alfven waves:
Fletcher & Hudson 2007,
Reep et al. 201835

Numerical Approach to combine micro andmacro scales for comparison with observations
Multi-zone model:
Pick up the important regions (“zones”) for shaping
electron energy spectra (acceleration, trapping, etc.).

Propagationof accelerated
particles

X

Solve the approximated Fokker-Planck eq (e.g. Petrosian 2012)
for multi-zones,

N(E) : electron energy
distribution function

Escape to
the next zone

Injection fromthe previous zone

Using the multi-zone model, we can• Consider the propagation of electrons across multiple structures• Examine/test different acceleration mechanisms
by trying corresponding coefficients (A, DEE, etc) for each zoneà Identify electron acceleration/propagation processes throughcomparisons with observations

A key task of numerical & analytical studies:
Identify important zones and derive effective coefficients

Numerical Approach in macro scale
MHD for understanding of ambient plasma
MHD simulation of a solar flare (magnetic reconnection)

Takasao et al. (2012)

calculated by Kaneko

pl
sh
as
oc
m
k
oi
d

ou
tf
lo
w

cu
sh rrenee ttPossible acceleration sites

Chen et al. (2015)37

Numerical Approach in macro scale
MHD + GCA for understanding of particle acceleration
calculated by Kaneko

Case 1Case 2

Case 1Case 2

Case 3

Case 338

Numerical Approach in macro scale:detailed MHD modeling of the above-the-loop-top region
2D model of Takasao & Shibata 2016

Density

3D model (without heat conduction. By Shibata-san, Osaka U.)|J|

pressure

Magnetictuning fork
Magnetic tuning fork oscillation locally produces turbulenceeven when the reconnection outflow is laminar (possibly as a result of ballooning instability)
à We will examine the impact on the stochastic acceleration and trapping via turbulence39

Numerical Approach in macro scale
MHD + GCA for understanding of particle acceleration
calculated by Kaneko

3D calculation in the realistic
magnetic fields during a solar flare.
40

Numerical Approach in micro scale
PIC for understanding of micro-scale physics

41

Numerical Approach [Emission model]
for comparison
%$ &#%*$ 
betweenobservation
andnumerical simulation
The simula*on
is conducted in Observa*onmode** Only the events that the produced photons emibed to outside of theWorldare recorded.

calculated by Nagasawa

electron

emi@ed gamma ray

interacting point
40000 km

 '"'$  $2020/11/26

2020

Input Electron spectrum
H$ = H$% I !&13

Normalized Counts

Normalized Counts

Solar corona modelin ComptonSoft
!$"%

40000 km

Photon Spectrum

2.0!!"# = 100 keV

4.0

3.0
Energy [keV]Electron index = 2.0

Electron index = 3.0

Energy [keV]Electron index = 4.042

Iteration between
observation and numerical simulation
Observation
X-ray spectrum
Magnetic field

Photon spectrum

Initial condition

Global plasma structure

Emission Model

Numerical Simulation

MHD scale ßà Particle scale

Energy spectrum

43New observational
approach

Focusing Imaging-Spectroscopy
in soft and hard X-rays
Spectro-Polarimetry
in soft Gamma-rays

x, t, E, pol

Numerical
approach
MHD+GCA
PIC
Emission model

La

Sp
bo

ra

So
to

la

ry

r

ac

Ph

A
e

ys

Ph

ic

st

ys

ro

ic

s

ph

ys

ic

s

Interdisciplinary
approachsParticle Acceleration
Magnetic Reconnection

Science Objectives of PhoENiX mission
1. Identify particle acceleration sites
in solar flares [where]
2. Investigate temporal evolution ofparticle acceleration [when]
3. Characterize properties ofaccelerated particles [how]planned to be realizedin Solar Cycle 26 (2030’)
44

Interdisciplinary approachwith strength and heritage of each research field• Space Physics• Observation in interplanetary space(trace of plasmas from the sun)
• PIC simulation• Astrophysics• X-ray & gamma-ray observations• X-Ray Spectral Fitting Package(Xspec)• X-ray emission model• Key technologies

Common Physics• Particle Acceleration• Magnetic Reconnection• Solar Physics• Laboratory plasma physics• Laboratory experiment of MR• Solar observations• MHD simulation• Key technologies
45

SolFER (Solar Flare Energy Release)– NASA funded Drive Science Center

1. Fast Release Mechanisms
2. Onset of Energy Release
3. Energization of Electrons
4. Energization of Ions
5. Particle Transport
6. Plasma Heating
PhoENiX can contribute toand collaborate with these
topics.

46

PI/Co-I Name

Major responsibilities

Affiliationin Pre-phase A1ain Pre-phase A1b and A2

Noriyuki Narukage

NAOJ

Project leadPrincipal Investigator (PI)

Mitsuo Oka

UCBMission science study

Project Scientist (PS)

Yasushi Fukazawa

Hiroshima U.

SGSP science study

Project Scientist (PS)Shin Watanabe

ISAS/JAXA

System study

Mission system leadKeiichi Matsuzaki

ISAS/JAXA

System study, SXIS design study

Mission system lead

Taro Sakao

ISAS/JAXASXIS science & design study, System study

SXIS lead, mirror study

Lindsay GlesenerU. Minnesota

HXIS US contribution study

HXIS U-lead, mirror study

Kouichi Hagino

Tokyo Univ. of Science HXIS science study

HXIS J-lead, camera study

Tsunefumi Mizuno

Hiroshima U.

SGSP science study

SGSP lead, detector study

Masanori Ohno

Eötvös U.

SGSP science study

SGSP lead

Kazuto Yamauchi

Osaka U.

SXIS mirror study

SXIS mirror study

Satoshi Matsuyama

Nagoya U.

SXIS mirror study

SXIS mirror study

Masayuki Ohta

ISAS/JAXASXIS/SGSP detector study

SXIS/SGSP detector study

Ikuyuki Mitsuishi

Nagoya U.

Pre-filter and HXIS mirror study

Pre-filter and HXIS mirror study

Säm Krucker

UCB/FHNWSXIS/HXIS US+Swiss contribution study,
HXIS design study

SXIS/HXIS US+Swiss contribution study,
SXIS/HXIS design & science study

Tom Woods

LASP, Colorado U.

SXIS/HXIS US contribution studyTeam
members
太陽物理

高エネルギー
宇宙物理

地球・惑星磁気圏プラズマ
物理実験室または核融合プラズ
マ物理

工学など、
左記以外

Collaborator nameAffiliation

Yoshinori Suematsu

NAOJ

SXIS mirror study

Area of collaboration

Satoshi Miyazaki

NAOJ

SXIS detector study

SXIS/HXIS US contribution study,
SXIS/HXIS design & science study

Shin’ichiro Takeda

Kavli IMPU

HXIS design & science study

Hiromitsu Takahashi

Hiroshima U.

SGSP design & science study

Amir Caspi

SwRI

SXIS science study

SXIS design & science study

Takao Kitaguchi

RIKEN

SGSP design & science study

Steven Christe

NASA/GSFC

HXIS design study

HXIS design & science study

Takashi Minoshima

JAMSTEC

SXIS/HXIS science study with simulations

Amy Winebarger

NASA/MSFCSXIS/HXIS US contribution study

SXIS/HXIS US contribution study & science study

Shinsuke Imada

Nagoya U.

SXIS science study

Patrick Champey

NASA/MSFC

HXIS mirror study

HXIS mirror study

Yoshiyuki Inoue

RIKEN

SGSP/HXIS science study

Wayne Baumgartner

NASA/MSFC

HXIS mirror study

HXIS mirror study

Kyoko Watanabe

NDA

Science study

Bin Chen

NJIT

SXIS/HXIS science study, Radio observation study

SXIS/HXIS science study, Radio observation study

Takuma Matsumoto

Nagoya U.

Science study

Alexander Warmuth

AIP

SXIS/HXIS science study, DLR contribution study

SXIS/HXIS science study, DLR contribution study

Haruhisa Iijima

Nagoya U.

Science study

Tomoko Kawate

NIFS

Science study

SXIS/HXIS/SGSP science study

Satoshi Kasahara

Tokyo U.

Science study

Masumi Shimojo

NAOJ

SXIS science study

SXIS science study

Tomoki Kimura

Tohoku U.

Science study

Takafumi Kaneko

Nagoya U.

SXIS/HXIS science study with simulations

SXIS/HXIS science study with simulations

Aya Bamba

Tokyo U.

Science study

Natasha Jeffrey

Northumbria U.

SGSP science study

SGSP science study

Teruaki Enoto

RIKEN

Science study

Satoshi Masuda

Nagoya U.

Science study

Science study

Herman Lee

Kyoto U.

Science study

Shinsuke Takasao

Osaka U.

Science study

Science study

Yoko Tsuboi

Chuo U.

Science study

Iain Hannah

U. Glasgow

Science study

Science study

Ryo Yamazaki

Aoyama Gakuin U.

Science study

Seiji Zenitani

Kobe U.

Science study

Science study

Yutaka OhiraTokyo U.

Science study

Takuma Nakamura

IWF/ ÖAW

Science study

Science study

Toshihiro Obata

Tokyo U.

System advisory

Hiroshi Tanabe

Tokyo U.

Laboratory-based science study

Laboratory-based science study

Kazunari Shibata

Kyoto U.

Science advisory

Munetaka Ueno

JAXA

N/A

System advisory

Yoshifumi Saito

ISAS/JAXA

Science advisory

Takeshi Takashima

ISAS/JAXA

System study

Science advisory

Kazuhiro Nakazawa

Nagoya U.

Science advisory

Iku Shinohara

ISAS/JAXA

Science advisory

Science advisory

Yoshizumi Miyoshi

Nagoya U.

Science advisory

Toshio Terasawa

NAOJ

Science advisory

Science advisory

Masahiro Hoshino

Tokyo U.

Science advisory

Hiroyasu Tajima

Nagoya U.

Science advisory

Science advisory

Kazutaka Yamaoka

Nagoya U.

Science advisory

Tadayuki Takahashi

Kavli IMPU

Science advisory

Science advisory

Yasushi Ono

Tokyo U.

Laboratory-based science advisory

Kuniaki Masai

TMU

Science advisory

Science advisory

Masaaki Yamada

Princeton U.

Laboratory-based science advisory

Laboratory-based science advisory47

Extra Science
Beyond the PhoENiX Scientific Objectives

48

pl
sh
as
oc
m
k
oi
d

cu
sh rre
ee nt
t
ou
tf
lo
w

Contribution to
Coronal Heating (thermalization) &Space Weather (Impulsive SEP, CME onset, pre-flare heating)

Magnetic
reconnection

Magnetosphericand Ionosphericdisturbance

Plasma cloudInterplanetary
space
Magnetic
EnergySpace
Weather

CME, Jet

Shock

Downflow

Termination
shock

Solar surface

Kinetic
Energy(Bulk motion)

Non-thermal
EnergyRadiation
EnergyCoronalHeating

Plasmoid

Shock Acc.?

Multiple X-line?
ThermalEnergyAccelerated
Particles

Thermal pool

Statistical Acc.?
Single X-line?
FACT: > 50 % of energy
released by MR is spentfor particle acceleration

Particle
Acceleration

Non-thermal
EnergyTrapping inloop

Accelerated
Particles

Chromosphericevaporation &condensation

Flaring loop,
etc.

ThermalEnergy49

Observation of CME and astronomical objects
PhoENiX can observe
the CME and astronomical objects
near the ecliptic plane (within 5 degree).

Gamma rays

Credits: eCUIP and ISDC

Balbo+ 2011

CME

Carb Nebula

Scorpius X-1
50

Interdisciplinary approachfor the understanding of plasma physics beyond individual research field
Maximum Energy

Magnetic Reconnection

Flare

Makishima (1999)

Ji & Daughton (2011)

Shibata & Yokoyama (1999)

51

One-Page Ideas

PhoENiX team is looking foryour scientific ideasthat is wanted to be realizedwith
X-ray imaging spectroscopic
and soft gamma-ray
spectropolarimetricobservations for solar flares,
i.e., by PhoENiX mission.
https://phoenix-project.science/one-page-idea

52

Schedule of PhoENiX

y
da
To

IS

um
im
ax
rM
la
X
So
Ni
5
oE
03
Ph
~2
of
ch
un
?
La
I-5
XS
33
FO
20
of
ch
un
La
T
?
VS
27
EU
20
of
ch
un
La
I-4
XS
26
FO
20
of
ch
un
La
al
os 小型
24
op 型
20
pr 募
n 公
io XA
i ss J A
M AS/
?
22
20

2021

53

Solar-C (EUVST) から PhoENiX へ
拡張した
PhoENiX のサイエンス

宇宙天気
磁気圏・電離
圏の擾乱
プラズマの
塊

惑星間空間

加速粒子の
運動
エネルギー

CME
ジェット

衝撃波

ダウン
フロー

終端衝撃波

加速粒子

太陽表面付近
磁気
エネルギー
プラズマの
塊の運動
エネルギー

磁気再結合

プラズ
モイド

放射
エネルギー

衝撃波加速？

プラズモイド加速？
熱
エネルギー

高温プラズ
マの溜り場

PhoENiX による粒子加速研究フレア
ループなど

Solar-C (EUVST)
による
精密プラズマ
診断

熱
エネルギー

統計加速？
電場加速？

コロナ
加熱

粒子加速

加速粒子の
運動
エネルギー

フレアループ
での閉じ込め加速粒子

彩層蒸発

X線で可視化された
太陽フレア

Science Objectives of PhoENiX mission
The universe is filled withHigh Energy (Accelerated) Particles!!

1. Identify particle acceleration sites
in solar flares [where]
2. Investigate temporal evolution ofparticle acceleration [when]“What is the origin ofHigh Energy Particles?”

3. Characterize properties ofaccelerated particles [how]The sun is unique in that:ü A natural laboratory of high energy plasmas
ü Mother of lifeü Impact on earth and social environments

ü Energization of space plasmas
ü Formation and evolution of lifeü Influence on planetary environments

Sounding Rocket FOXSI series

2012

2014

2018

NASA DRIVE Science Center

Solar Flare Energy Release
https://solfer.umd.edu/

planned to be realizedin Solar Cycle 26 (2030’)

New observational
approach

Focusing Imaging-Spectroscopy
in soft and hard X-rays
Spectro-Polarimetry
in soft Gamma-rays

x, t, E, pol2024
Flare campaign

Numerical
approach
MHD+GCA
PIC
Emission model

La

Sp
bo

ra

So
to

la

ry

r

ac

Ph

A
e

ys

Ph

ic

s

st

ys

ro

ic

s

ph

ys

ic

s

Interdisciplinary
approachParticle Acceleration
Magnetic Reconnection
55

https://indico.ipmu.jp/event/395/

56