WG 4 Multiwavelength Correlative Studies Group Members Marina

WG 4 Multi-wavelength Correlative Studies Group Members Marina BATTAGLIA Cristina CHIFOR Brian DENNIS Martin FIVIAN Lyndsay FLETCHER Iain HANNAH Hugh HUDSON Haisheng JI Joe KHAN Säm Krucker Helen MASON Ryan MILLIGAN Manuela TEMMER Mikko VÄÄNÄNEN Lidia van DRIEL-GESZTELYI Astrid VERONIG Alexander WARMUTH

RHESSI WG 4 – SCHEDULE Wednesday 11: 00 – 13: 00 RHESSI Thermal / low energy / multi-l spectroscopy 14: 30 – 18: 00 Footpoints Part I Thursday 09: 00 – 10: 30 Coronal sources, joint with WG 3 11: 00 – 13: 00 Footpoints Part II 14: 30 – 16: 00 Joint session with WG 2 – Oct 28 th event 16: 30 – 18: 00 Joint with WG 5 – soft-hard-soft, number problem, etc. Friday 09: 30 – 11: 00 Energetics

RHESSI Observations of the Iron-Line Feature v. From Fe line complex at 6. 7 ke. V, compared to continuum we have a handle on the Fe/H abundance ratio. v. How does the empirical Fe/H abundance ratio in flares vary with Te ? v How do empirical correlation curves compare with theoretical curves calculated with coronal Fe abundances ? v. Survey of ~ 30 RHESSI flares (C 3 - X 5) v Fe line features observed by RHESSI at 6. 7 ke. V indicate a coronal abundance of Fe Discrepancies could be due to: instrumental effects, non-isothermality errors in atomic rates CHIFOR/PHILLIPS/DENNIS

RHESSI Quiet Sun Offpointing Offpoint RHESSI from Sun to modulate QS signal and separate from background: noise limited or signal ? – ~667 hrs off sun (so far), 127 hrs useful (20%), 63 hrs<A 1(9. 5% – So far, have observed Quiet Sun with hot coronal loops in SXI/EIT • New limits in 3 -17 ke. V – correlates with GOES in 3 -7 ke. V QS signal detected? – Fit Hot T, low EM (5 -7 MK, 1044 cm 3) or steep power-law (<-7) • Comparable limits 17 -100 ke. V • What will we get with more offpointing during Solar minimum? HANNAH

PINT-of-ALE DEM Multi-instrument DEM • Ten RHESSI bins from 5 – 12 ke. V • Two GOES channels • Markov-Chain Monte Carlo method DEM exp(-T/T 0) uncertainties (colour bars) returned by MCMC analysis DENNIS/LI

Inter-instrument calibration: XSM+RHESSI XSM/RHESSI lightcurve 6 -8 kev XSM/RHESSI spectrum • XSM GOES calibrations OK • XSM/RHESSI low E needs factors explained • Messenger/XSM underway 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 X 3. 8 flare) RHESSI HXR sources occur only along certain parts of the Ha ribbon edges Higher local reconnection rates (factor 5 -10) at these sites HXR sources tend to avoid strongest magnetic fields and umbrae. Almost vertical inclination of field lines does not favour reconnection there? Peculiar motions/spatial jumps of HXR sources? Reconnection rises through field lines of different altitudes, with distant footpoint locations TEMMER

Reconnection rates and HXR characteristics VERONIG

Correlation of FP Motion with Deposited Energy • 2 -d model, sheet of area Ar Ar = Lh∙Lv = area of reconn. region • Correlation of Deposited Energy with Footpoint Separation July 23, 2002 LV 25 arcsec LV huge LV 100 arcsec • a = acceleration efficiency • Smooth correlation curve ‘accurate’ (=stable) FP positions and fits of spectra • Can derive the required current sheet vertical extent, Lv FIVIAN

Footpoint motions and flare shear Red contour: 30 -50 ke. V Blue contour: 3 -10 ke. V Green contour: 34 GHz The distance and velocity between the two Ha kernels The distance between the two HXR FPs The ‘height’ of the HXR loop top source The flare shear time profile The rate of change of flare shear JI

Coronal Sources in an occulted solar flare: 20 -Jul-2002 20 -30 ke. V 50 -100 ke. V 100 -200 ke. V Hard spectral index ~3. 0 l GOES+RHESSI gives density estimate of 2. 2 x 1011 cm-3. l Column depth will collisionally stop electrons with 30 -40 ke. V l How does > 100 ke. V emission arise? l BONE

Flux – Spectral Index correlations in coronal sources 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 index and non-thermal flux at 35 ke. V of coronal hard X-ray spectra BATTAGLIA/BENZ

Relativistic Shock Drift Acceleration (SDA) at the Reconnection 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 wave in Radio Is the ‘termination shock’ suggested by Warmuth et al a standing shock at all? Moreton/coronal wave seen in radio Dotted line: Edge of Ha Moreton wave 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)

Rising Coronal X-ray Source and Erupting Filament SOHO/CDS slit Fe XIX Doppler velocity Flux rope Vl<0 Cooling loops Vl>0 p o s i t i o n time • 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 van Driel/Goff et al +

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” ~ 300 km Orange=25 -50 ke. V Blue=WL • Very compact sources • Correlated in time and space with HXRs at 10 s of ke. V • Provide an independent diagnostic for energy deposited in atmosphere • Same order of magnitude as electron energy flux inferred from HXR thick target HUDSON/FLETCHER