WG4 Multi-wavelength Correlative StudiesGroup Members

Marina BATTAGLIACristina CHIFORBrian DENNISMartin FIVIANLyndsay FLETCHERIain HANNAHHugh HUDSONHaisheng JIJoe KHANSäm KruckerHelen MASONRyan MILLIGANManuela TEMMERMikko VÄÄNÄNENLidia van DRIEL-GESZTELYI Astrid VERONIGAlexander WARMUTH

Wednesday 11:00 – 13:00 RHESSI Thermal / low energy / multi

spectroscopy14:30 – 18:00 Footpoints Part I

Thursday 09:00 – 10:30 Coronal sources, joint with WG311:00 – 13:00 Footpoints Part II14:30 – 16:00 Joint session with WG2 – Oct 28th event16:30 – 18:00 Joint with WG5 – soft-hard-soft, number

problem, etc.

Friday 09:30 – 11:00 Energetics

RHESSI WG4 – SCHEDULE

RHESSI Observations of the Iron-Line Feature

Survey of ~ 30 RHESSI flares (C3 - X5) Fe line features observed by RHESSI at 6.7 keV indicate a coronal abundance of Fe

Discrepancies could be due to: instrumental effects, non-isothermalityerrors in atomic rates

From Fe line complex at 6.7keV, compared to continuum we have a handle on the Fe/H abundance ratio.

How does the empirical Fe/H abundance ratio in flares vary with Te ?

How do empirical correlation curves compare with theoretical curves calculated with coronal Fe abundances ?

CHIFOR/PHILLIPS/DENNIS

RHESSI Quiet Sun Offpointing

• New limits in 3-17 keV– correlates with GOES in 3-7 keV

QS signal detected?

– Fit Hot T, low EM (5-7MK, 1044cm3) or steep power-law (<-7)

• Comparable limits 17-100 keV• What will we get with more

offpointing during Solar minimum?

Offpoint RHESSI from Sun to modulate QS signal and separate from background: noise limited or signal ?– ~667hrs off sun (so far), 127hrs useful (20%), 63hrs<A1(9.5%– So far, have observed Quiet Sun with hot coronal loops in SXI/EIT

HANNAH

PINT-of-ALE DEM

DEM exp(-T/T0)

Multi-instrument DEM

• Ten RHESSI bins from 5 – 12 keV

• Two GOES channels

• Markov-Chain Monte Carlo method

uncertainties (colour bars) returned by MCMC analysis

DENNIS/LI

Inter-instrument calibration: XSM+RHESSI

• XSM GOES calibrations OK• XSM/RHESSI low E needs factors explained• Messenger/XSM underway

XSM/RHESSI lightcurve 6-8kev XSM/RHESSI spectrum

VÄÄNÄNEN/DENNIS

Propagating Brightenings Following Filament Eruptions

Brightenings parallel to flare ribbons were observed with RHESSI (Grigis + Benz)

Survey of brightenings associates with erupting filaments in EIT shows many examples of brightenings along arcade footpoints

Slow speeds correspond to slow eruptions

MASON/TRIPATHI

RHESSI-SOHO/CDS Observations of Chromospheric Evaporation

Plasma velocities observed with CDS during impulsive phase of 2 flares

•A high flux of non-thermal electrons high-velocity upflows and low-velocity downflows (explosive evaporation)

•A flux value an order of magnitude lower weaker upflows and no downflows (gentle evaporation)

MILLIGAN

Constraints from the magnetic field on HXR source motions (17-Jan-2005 X3.8 flare)

HXR sources tend to avoid strongest magnetic fields and umbrae.Almost vertical inclination of field lines does not favour reconnection there?

RHESSI HXR sources occur only along certain parts of the Ha ribbon edgesHigher local reconnection rates (factor 5-10) at these sites

Peculiar motions/spatial jumps of HXR sources? Reconnection rises through field lines of lines of different altitudes, with distant footpoint locations TEMMER

Reconnection rates and HXR characteristics

VERONIG

Correlation of FP Motion with Deposited Energy

July 23, 2002

LV 25 arcsec

LV 100 arcsec

LV huge

• 2-d model, sheet of area Ar

Ar = Lh∙Lv = area of reconn. region

• Correlation of Deposited Energy with Footpoint Separation

= acceleration efficiency

• Smooth correlation curve ‘accurate’ (=stable) FP positions and fits of spectra

• Can derive the required current sheet vertical extent, Lv FIVIAN

Red contour: 30-50 keVBlue contour: 3-10 keVGreen contour: 34GHz

The distance and velocity between the two H kernelsThe distance between the two HXR FPsThe ‘height’ of the HXR loop top source

The flare shear time profileThe rate of change of flare shear JI

Footpoint motions and flare shear

20-30keV 50-100keV 100-200keV

Coronal Sources in an occulted solar flare: 20-Jul-2002

Hard spectral index ~3.0 GOES+RHESSI gives density estimate of 2.2x1011cm-3.

Column depth will collisionally stop electrons with 30-40keV How does > 100keV emission arise?

BONE

RHESSI imaging - spectroscopy finds soft-hard-soft behavior in the coronal source of several flares might be a feature of the accelerator and not a transport effect

Time evolution of spectral indexand non-thermal flux at 35 keV of coronal hard X-ray spectra

Flux – Spectral Index correlations in coronal sources

BATTAGLIA/BENZ

Relativistic Shock Drift Acceleration (SDA) at theReconnection Outflow Termination Shock (TS)

theory: fast-mode standing shock in reconnection outflow

radio observations: signatures of TS are present

theory: relativistic shock drift acceleration at the TS

comparison of theory and observations: SDA at the TS can reproduce required electron fluxes & power

WARMUTH/MANN/AURASS

Moreton/coronal wave seen in radioDotted line: Edge of H Moreton wave

Moreton wave in Radio

Is the ‘termination shock’ suggested by Warmuth et al a standing shock at all?

PICK

WG 4+5

Flux – spectral index correlation (“SHS”) – presentation by Grigis on a transit-time damping model

Electron total numbers, fluxes, and predicted/observed response of atmosphere – discussion by all

Presentation by Pick on Type III bursts associated with compressing edge of a CME – new theoretical challenge (see Steven’s presentation)

• RHESSI coronal source at constant distance beneath filament – RHESSI source as result of interaction of upwards outflow jets with filament?

• CDS observations with slit above a rising filament + magnetic field extrapolations downflows of hot plasma along flare loop legs

• Rapid motion of filament into LASCO FOV implies exponential growth of CMEs in the low corona

Rising Coronal X-ray Source and Erupting Filament

SOHO/CDS slit

Vl>0

Vl<0Flux rope

time

position

Fe XIX Doppler velocity

Cooling loops

+

van Driel/Goff et al

CME vs. Flare Energies

0.1

1.0

10.0

100.0

1000.0

10000.0

0.01 0.1 1 10 100 1000

Flare Energy Component (1030 ergs)

CM

E K

ine

tic

En

erg

y

(103

0 erg

s)

SXR-Emitting Plasma - Ltotal TSI Increase (SORCE) Peak Thermal Energy (Upeak)Ions Equipartition Electrons

SORCE / TIM

28 October 2003 4 November 2003

23 July 200221 April 2002

3 Nov. 2003

Flare energetics

•Total radiated energy in SXR (LSXR) from GOES

•Total radiated energy from hot plasma (Lhot) from GOES T & EM.

•Total radiated energy from SORCE (Ltotal)

•CME KE from LASCO

Ltotal ~ KECME

~ 10 Lhot

~ 100 LSXR

DENNIS

White Light Flares and Energetics

1 px = 0.5” ~ 300km

Orange=25-50keV

Blue=WL

• Very compact sources

• Correlated in time and space with HXRs at 10s of keV

• Provide an independent diagnostic for energy deposited in atmosphere

• Same order of magnitude as electron energy flux inferred from HXR thick target

HUDSON/FLETCHER