NGSPM-SOT
Topic-I:
Formation mechanisms of chromosphere,corona, and solar wind
Kiyoshi Ichimoto (Kyoto-U./ NAOJ)
Toshifumi Shimizu（ISAS/JAXA）, Bellot Rubio (IAC),
Mats Carlsson (Oslo), Ted Tarbell (LMSAL), John Raymond (SAO)Science objects of Solar-C (revised)
I. Formation mechanism of chromosphere, corona and solar windI-1

Origin of chrom.jets and heating

Foot point B topology, shock, twist,,

I-2

Nano-flare heating

Tiny brightening, non-thermal plasma

I-3

Wave heating

Wave mode, energy flux, dissipation

I-4

Solar wind acceleration

B topology in CH, Alfven wave in corona

I-5

Mechanism of prominence

B field structure, mass circulation

II. Physical origin of large-scale eruptions and algorithm for prediction
II-1

Energy storage

Photo./chrom. B field maps

II-2

Trigger mechanism

Emerging flux, interaction with chrom.B

II-3

Mechanism of explosion

Large scale dynamics, current system

II-4

Physics of fast reconnection

Current sheet, plasmoid, shock

III. Origin of solar cycle and space climate variability
III-1

Mechanism of UV variability

UV emissions at fine scale B structureIII-2

Grow/decay of AR, flux transport Emergence/submergence of flux

III-3

Origin of alpha effect

Small scale & large scale helicity

I. Formation mechanisms ofchromosphere, corona, and solar wind
Sub-objectives;
1. Formation mechanism of spicules and their influencein the corona
2. Nanoflare heating
3. Wave heating
4. Acceleration mechanism of solar winds
5. Formation mechanism of prominence
6. Role of vortex motions on energy transport
7. Non-ideal MHD effect on the heating
8. Mechanism of flux emergenceTopic IV fundamental plasma processes• Magnetic reconnection• Non-ideal MHD effect• Wave generation, propagation and dissipation• Particle acceleration• MHD instability• MHD turbulence1. formation mechanism of spicules andtheir influence in the coronatask

Key observation

requirements

instrument

I-1-1: Observe magnetic topology anddynamics at the foot point of spicules
to see the discontinuity and shears ofmagnetic structure, and observe theinteraction of magnetic field andconvection by which those topologies
are formed.
I-1-2: Observe propagation of slow
mode MHD waves and/or torsionalAlfvén waves along spicules, andidentify driving mechanism of jetsand evaluate the heating inchromosphereI-1-3: Observe the response of coronal
above the spicule and measure thesupplied mass and thermalization
process・Images and velocity field resolving
photospheric magnetic elements
・Vector magnetic fields fromphotosphere to the base of chromosphere
・FOV to cover several spicules withhigh cadence

Spectro-pol. e ~ 10-4
Dx ~ 0.1” , FOV > 10”
T: 5000 ~ 10000K
Dt < 20s, Time span ~ 2hr

SOLAR-C/SUVIT
1.4m
DKIST
ESTSunrise-3・Images and velocity fields resolving
magnetic elements in photosphere toupper chromosphere with chromosphericvector magnetic fields
・Comparison of observations withdifferent view angle μ (= cos θ)・TR-corona images and velocity fields
resolving elementary structures of TR ~corona at multiple temperatures(105~5×106K)
・Comparison of disc and limb
observations
・Images and velocity fields resolving
magnetic elements in photosphere toupper chromosphere with chromosphericvector magnetic fields
・Comparison of observations withdifferent environments: AR, QS, and CH.

Spectro-pol. e ~ 10-4
Dx ~ 0.1” , FOV > 20”
T: 5000 ~ 10000K
Dt < 20s, Time span ~ 2hr

SOLAR-C/SUVIT
1.4m
DKIST
ESTSunrise-3

Dx ~ 0.3” , FOV > 50”
T: 105~5×106K
Dt < 20s, Time span ~ 5hrl/Dl ~ **SOLAR-C/EUVST/HCI

Spectro-pol. e ~ 10-4
Dx ~ 0.1” , FOV > 20”
T: 5000 ~ 10000K
Dt < 20s, Time span ~ 2hr
Total duration ~ 200hr

SOLAR-C/SUVIT
1.4m
DKIST
ESTSunrise-3

I-1-4: Derive statistical properties ofthe spicules from the viewpoint ofenergizing and structuring the entire
solar atmosphere, and understandtheir role in different environments.

2. Verify the Nanoflare hypothesistask

Key observation

requirements

instrument

I-2-1: Observe tiny brightening in TR
and corona with sensitivity of ~ 1022
erg, determine the power-law energy
spectrum down to ~ 1022 erg, andverify the total deposited thermalenergy in active regions.
I-2-2: Observe intermittent process toproduce 107K temperature plasmas
and high velocity plasma motions

・High sensitivity images resolving
elementary structures of TR ~ corona at
multiple temperatures (105~107K)

Dx ~ 0.3” , FOV > 300”
T: 105~107K
Dt < 20s, Time span ~ 5hr

SOLAR-C/HCI・Images and velocity fields resolving
elementary structures of TR ~ corona at
multiple temperatures (105~107K)

SOLAR-C/EUVST/HCI

I-2-3: Observe time-series of subarcsec structures in corona and verify
relations of tangling structures andnanoflaresI-2-4: Verify causal relations between
nano-flares and photosphericmagnetic activity caused byconvection and consequent changes ofchromospheric magnetic fields

・Images resolving elementary
structures of TR ~ corona at multiple
temperatures (105~5×106K)

Dx ~ 0.3” , FOV > 50”
T: 105~107K
Dt < 20s, Time span ~ 5hrl/Dl ~ **Dx ~ 0.3” , FOV > 50”
T: 105~5×106K
Dt < 20s, Time span ~ 5hr
Spectro-polarimetry e ~ 10-

SOLARC/SUVIT+HCI
DKIST+(EUV)・Simultaneous high resolution
observations of photosphere,
chromosphere, and corona・Photospheric magneto-convective
activity and chromospheric response
・FOV to cover several supergranulation cells

4Dx ~ 0.1”- 0.3” , FOV >50”
T: 5000 ~ 5×106K
Dt < 20s, Time span ~ 5hr

SOLAR-C/HCI3. Verify the Wave heatingtask

Key observation

requirements

instrument

I-3-1: Measure time-series of physicalquantities at different heights inphotosphere-chromosphere-corona
with sub-arcsec resolutions,investigate amplitude vs. phasecorrelation by not only event studies
but also statistical studies, andevaluate wave modes and energy
fluxes in frequency domain
1-3-2: Observe discontinuous
structures of motions and physicalquantities in chromsophere andcorona to see non-linearization
processes
I-3-3: Observe TR & coronal response(plasma motions and temperaturechanges) in fine structures to waves
propagating from below, and verify
thermalization process

・Simultaneous images andvelocity/magnetic field observations ofphotosphere, chromosphere, and corona,resolving their elementary structures
・Cadence to catch up wave propagation
・Comparison of observations withdifferent view angle μ (= cos θ)Spectro-polarimetry e ~ 10-

SOLAR-C
Sunrise-3 +corona・Images and velocity fields resolving
elementary structures in chromosphere ~coronaDx ~ 0.1”- 0.3” , FOV >30”
T: 5000 ~ 5×106K
Dt < 20s, Time span ~ 5hr

SOLAR-C
Sunrise-3 +corona・Images resolving elementarystructures of TR ~ corona at multiple
temperatures (105~5×106K)

Dx ~ 0.3” , FOV > 30”
T: 105~5×106K
Dt < 20s, Time span ~ 5hr

SOLARC/EUVST/HCI

I-3-4: Observe large scale travelingwaves in corona (by using
chromospheric features i.e. filaments
or prominences), and evaluate theirmodes and energy fluxes

・Images and velocity field ofprominence ~TR ~ corona at multiple
temperatures (104~5×106K)

Dx ~ 0.3” , FOV > 200”
T: 104~5×106K
Dt < 20s, Time span ~ 5hr

SOLAR-C

4

Dx ~ 0.1”- 0.3” , FOV >30”
T: 5000 ~ 5×106K
Dt < 20s, Time span ~ 5hr
Total duration ~ 200hr

4. Understand the formation mechanismof solar winds
task

Key observation

requirements

instrument

I-4-1: Observe magnetic fields inphotosphere and chromosphere undercoronal holes that initiate solar winds,and determine geometry of flux tubes
connected to corona

・Vector magnetic fields resolving
photospheric and chromosphericmagnetic elements under coronal holes

Spectro-polarimetry e ~ 10-SOLAR-C

I-4-2: Identify relations of source
regions of fast solar winds andcoronal density structure (plumes)

・Images and velocity fields resolving
elementary structures of corona at
multiple temperatures (105~5×106K)
・wide FOV covering coronal holes・Time-series of high-resolution coronal
images and velocity fields
・Time cadence of ~10 seconds tomeasure periods of waves
Measure the intensity of spectral
lines from different FIP elements atcorona base and compare with insitu measurements
High sensitivity

I-4-3: Confirm propagating coronal
Alfvén waves and measure theirenergy fluxes
I-4-4: Identify the source regions ofsolar winds.

I-4-5: Observe the anisotropy oftemperature and turbulence at thecoronal base.

4Dx ~ 0.1”- 0.3” , FOV >30”
T: 5000 ~ 5×106K
Dt < 20s, Time span ~ 5hr
Dx ~ 0.3” , FOV > 300”
T: 106~5×106K
Dt < 20s, Time span ~ 5hr

SOLARC/EUVST/HCI

Dx ~ 0.3” , FOV > 300”
T: 106~5×106K
Dt < 20s, Time span ~ 5hr

SOLARC/EUVST/HCI

Dx ~ 1” , FOV > 300”
T: 106~5×106K
Dt ~ 1hr, Time span ~ 5hr
Sensitivity??

Solar Orbiter
SOLARC/EUVST

Solar Orbiter
SOLARC/EUVST

5. Understand the prominence formation
mechanismtask

Key observation

requirements

instrument

I-5-1: Measure magnetic structure
supporting prominences

・Magnetic fields inside prominences
・Photospheric magnetic fields below
prominences
・Comparison of AR vs QS and disk vslimb observations

Spectro-polarimetry e ~ 10-

SOLAR-C/SUVIT
ASOT
Medium size
ground telescopes・Images and velocity fields ofprominences (104K)
・Images and velocity fields resolving
elementary structures of TR ~ corona
surrounding prominences at multiple
temperatures (105~5×106K)
I-5-3: Track evolution of photospheric ・Photospheric velocity fields and vector
and chromospheric magnetic fields magnetic fields
near neutral lines, and clarify ・High-resolution images, velocity
condition of prominence formation
fields, and magnetic fields ofchromosphere・wide FOV continuous observation forseveral days
I-5-2: Detect mass circulation among
chromosphere – prominence - corona

4Dx ~ 0.3” , FOV > 300”
T: 5000 ~ 104K
Dt < 10min, Time span ~5hr
Dx ~ 0.1”- 0.3” , FOV >300”
T: 5000 ~ 5×106K
Dt < 60s, Time span ~ 10hr
Spectro-polarimetry e ~ 104

Dx ~ 0.3” , FOV > 300”
T: 5000 ~ 104K
Dt < 10min, Time span ~5day

SOLAR-C

SOLAR-CASOT

6. Understand the role of vortex motions
on energy transporttask

Key observation

requirements

instrument

I-6-1: observe small scale kinetic andcurrent helicity in photosphereI-6-2: twisting magnetic field inchromosphereI-6-3: propagation into the corona anddissipation

7. Understand the non-ideal MHD effect(ambipolar effect) on the heatingtask

Key observation

requirements

instrument

I-7-1: Measure differences between
dynamics of neutral atoms and ionsin MHD waves, and verify the effectof neutral atoms on the damping of
the wave・Images and velocity fields in ion andneutral atoms resolving spatial andtemporal scale of decoupling of neutral
atoms from plasma
・Choromospheric vector magnetic andelectric fields

Spectro-polarimetry e ~ 10-

SOLAR-C/SUVITDKIST
EST

4Dx ~ 0.01” , FOV > 20”
Dt < 1sec, Time span ~ 2hr
T: 5000 ~ 104K
Multi-lines of ion & neutralatom

8. Mechanism of flux emergencetask

Key observation

requirements

instrument

Spicule and waves
I-3-4: large scale traveling waves incorona, their modes and energy fluxes

I-1-3: coronal response tospicules

I-3-3: TR & coronal response towaves propagating from below
I-3-2: shock front and nonlinearization processes in chromos.

I-1-2: slow mode/ torsional
wave propagating along spicule

I-3-1: wave mode and energy flux in
sub-arcsec resolution

I-1-4: statistical properties of the spicules
and their role in formation of large scalestructures

I-1-1: magnetic field topology anddynamics at the foot point of spicules, andphotospheric activities as their sourceNano-flare heating
I-2-2: Observe intermittent process toproduce 107K temperature plasmas andhigh velocity plasma motions
I-2-3: Observe time-series of sub-arcsec
structures in corona and verify relations oftangling structures and nanoflares

Log(freqency）？

I-2-4: Verify causal relations between
nano-flares and photospheric andchromospheric magnetic activities

observation
Log（energy）

I-2-1: determine the energy spectrum down
to ~ 1022 erg to verify the total depositedthermal energy

Solar windI-4-4: Identify the source regions of solar
winds observed by in-situ measurements

I-4-3: Confirm propagating coronal Alfvén
waves and measure their energy fluxes

I-4-5: Observe the anisotropy of temperatureand turbulence at the coronal base.

I-4-2: Identify relations of source regionsof fast solar winds and coronal density
structure (plumes)

I-4-1: magnetic fields configuration inphotosphere and chromosphere undercoronal hole

Cranmer and van ballegooijen 2005

prominence

I-5-2: Detect mass circulation among
chromosphere – prominence - corona

I-5-1: Determine magnetic structurethat supports the prominences

I-5-3: Track evolution of photospheric andchromospheric magnetic fields near neutrallines, and clarify condition of prominence
formation

Role of vortex

I-6-3: propagation into the corona anddissipation

I-6-2: twisting magnetic field inchromosphereI-6-1: small scale kinetic and current
helicity in photosphere

Iijima+2015

Spicule and waves; what is needed?
I-3-4: large scale traveling waves incorona, their modes and energy fluxes
I-3-3: TR & coronal to waves
propagating from below,

I-1-3: coronal response tospicules Solar-C/HCI,EUVST

Corona images & spectroscopy
Dx ~ 0.3” , FOV > 50”,
Dtslow< 20s,
Timetorsional
span ~ 5hr
I-1-2:
mode/
wave propagating along spicule

Corona /prominence images & Doppler
Solar-C/
Dx ~ 0.2-0.3” , FOV > 300”,
Dt <shock20s, front
Timeandspan~ 1dy
SUVIT,EUVST
I-3-2:
nonlinearization processes

Small mission?

I-3-1: wave mode and energy flux in
sub-arcsec resolution

Large volume of samples atvarious locations on the sun

Image/vector magnetic field ofphotosphere & chromosphereDx ~ 0.1-0.3” , FOV > 10”, e ~ 10-3~10-4
Dt < 20s, Time span ~ 2hr

DKIST, Sunrise-3, GREGOR, SST,
Solar-C/SUVIT
I-1-1: magnetic field topology andI-1-4: statistical properties of the spicules
and their role in formation of large scale
structures

dynamics at the foot point of spicules, andphotospheric activities as their sourceNano-flare heating; what is needed?
Corona spectroscopy
Dx ~ 0.3” , FOV > 50”, T: 105~107K
Dt < 20s, Time span ~ 5hr

I-2-2: Observe intermittent process toproduce 107K temperature plasmas andhigh velocity plasma motions

Solar-C/EUVST, HCI

I-2-3: Observe time-series of sub-arcsec
structures in corona and verify relations oftangling structures and nanoflares

Image/vector magnetic field ofphotosphere & chromosphereDx ~ 0.1-0.3” , FOV > 50”, e ~ 10-3~10-4
Dt < 20s, Time span ~ 5hr

I-2-4: Verify causal relations between
nano-flares and photospheric andchromospheric magnetic activities？

Log(freqency）

Solar-C/SUVIT, DKIST, Greg..

Solar-C/HCIHigh sensitivity corona image
Dx ~ 0.3” , FOV > 300”,
observation
Dt < 20s, Time span ~ 5hr
Log（energy）

I-2-1: determine the energy spectrum down
to ~ 1022 erg to verify the total depositedthermal energy

spectroscopy
Solar wind; what is Coronalneeded?
Abundance of different FIP elements

Solar-C/EUVST, HCI
Corona images & spectroscopy
Dx ~ 0.3” , FOV > 300”, Dt < 20s,
Time span ~ 5hr
I-4-3: Confirm propagating coronal Alfvén
waves and measure their energy fluxes
I-4-2: Identify relations of source regionsof fast solar winds and coronal density
structure (plumes)

Stereoscopic obs.
Dx ~ 0.3” , FOV > 300”, Dt ~ 1hr,
Time span ~ 1week

Solar-C/EUVST, HCI
I-4-4: Identify the sourceof solar+ SO,regions
Sol.Probewinds observed by in-situ measurements

I-4-5: Observe the anisotropy of temperatureand turbulence at the coronal base.
Image/vector magnetic field ofphotosphere & chromosphereDx ~ 0.1-0.3” , FOV > 100”, e ~ 10-3~10-4
Dt < 20s, Time span ~ 5hrSolar-C/SUVIT
I-4-1: magnetic fields configuration inphotosphere and chromosphere undercoronal hole

Cranmer and van ballegooijen 2005

prominence; what isimages
needed?
and velocity fields of TR ~ corona
Solar-C/EUVST/HCI

T = 105 ~ 5x106K
Dx ~ 0.3” , FOV > 300”,
Dt < 1min, Time span ~ 10hr

I-5-2: Detect mass circulation among
chromosphere – prominence - corona

Solar-C/SUVIT
Image/vector magnetic field ofphotosphere & chromosphereDx ~ 0.1-0.3” , FOV > 300”, e ~ 10-3~10-4
Dt ~ 30min, Time span ~ 1weeks

Vector magnetic field of prominenceDx ~ 0.3” , FOV > 300”, e ~ 10-3~10-4
Dt < 30min, Time span ~ 5hr
I-5-1: Determine magnetic structurethat supports the prominences

I-5-3: Track evolution of photospheric andchromospheric magnetic fields near neutrallines, and clarify condition of prominence
formation

Role of vortex; what is needed?
Corona images & spectroscopy
Dx ~ 0.3” , FOV > 300”,
Dt < 20s, Time span ~ 5hrSolar-C/EUVST/HCI, SMEX?

I-6-3: propagation into the corona anddissipation

Image/vector magnetic field of chromosphereDx ~ 0.1” , FOV > 50”, e ~ 10-3 ~ 10-4
Dt ~ 10sec, Time span ~ 2hr

I-6-2: twisting magnetic field inchromosphere

Iijima+2015

DKIST, Sunrise-3,Solar-C/SUVIT
Image/vector magnetic field of photosphereDx ~ 0.1” , FOV > 50”, e ~ 10-3
Dt ~ 10sec, Time span ~ 2hr
I-6-1: small scale kinetic and current
helicity in photosphereSpatial and temporal scales covered by SUVIT and DKIST
400”

Large scale structures, explosions

200”

Spatial scale

100”

50”

Active region,
prominence

Flare, eruption

Ubiquitous finescale dynamics

0.1”

0.05”

Sunspot, super
granulation

Space telescopes

spiculeFlux tube

substructure?

Large ground telescope

Connection between small scale and large scale
Time scale