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6-8 December 2005, Wroclaw ROUND TABLE DISCUSSION DRAFT NOTES by Cristina Chiffor ROUND TABLE DISCUSSION I (led by Mason) DEM ANALYSIS Urnov: * worth to start by comparing different methods * select events with simultaneous observations Sylwester J. and Urnov to exchange data and compare 2 DEM inversion methods. Sylwester J.'s inversion method different from CHIANTI method. Two different codes, same method used in Sylwester J.'s group. Phillips: * RHESSI spectra not fitted by 1 T (especially in flare rise stages) * Pint of Ale code used RHESSI spectra * analytic form of DEM used for Si XIII, Si XII satellites (Phillips, Sylwester J., Sylwester B., Sylwester J.) Sylwester J.: * multi-thermal nature of flares. Start from assuming many thermal kernels. Reale: * important to select the right events. Complex flares are interesting but maybe better to start with simpler ones. Comment from Mason: 'compact' might not mean simple but not being resolved properly * subtraction of coronal background important for ARs (not as much for flare Ts) Sylwester J.: * background subtracted pre or post flare. However, this was not done for the analysis of Si lines. Phillips: * comment on the meaning of 'simple' flares. One always observes see many arcades of loops. Comment from Reale: loop arcades present in the decay phases. Flare peak brings complications due to non-equilibrium effects. Identified project to compare different DEM methods with agreed data (possible benchmarking with tokamak DEM) * DEM shape can tell us about flare heating. i.e. peaked DEM means heating mostly at footpoints; smooth DEM means heating is distributed more uniformly in the structure. Comment from (?) on the decay phases of QSS flares: should not select flares on the basis of geometry (they might have more complicated physics). Start with long duration effects. * DEM = starting point to understanding how important non-thermal components are. Is there clear definition? How to diagnose ? What is the importance? Multi-thermal does not mean non-Maxwellian. Sylwester J.: * dielectronic satellites sensitive to presence of non-thermal effect at right energy. * experimental results come from laboratory calibration. Urnov: * DEM EUV lines not sensitive to non-thermal contributions. One needs to compare results from X-rays and EUV. Dzifcakova: * non-Maxwellians have mild effect on line intensities but a major effect on non-ionization equilibrium. Urnov: * satellite lines important because one can say if non-thermal effects exist or not * identified need for a self consistent solution for lines. If inconsistent, possible indicator of non-thermal effects. * RESIK list of abundances to be compiled (Jan 1st - Mar. 14th 2003). So far there have been fluorescence problems. Routines to fit all existing spectra in the database in a semi-automated procedure. Already calculated abundances for Si, Ar, K. Variations up to 2 orders of magnitude. Abundances in flares relate to where heating takes place. Landi: * Comment on SUMER being appropriate for studying abundances. Separate rise, decay flare phases, quite sun periods (for RESIK abundances). - CORONAS-F/ RESIK + SPIRIT - RHESSI What is the current status of databases and s/w? How widely used are the databases? How easily accessible are the data? What are the future plans? What other issues are there relating to data access, s/w and documentation RESIK data (Jan - Mar 2003 fluorescence): initially, .sav files to be made available online (password protected). Possibly FITS files later on. SPIRIT and RHESSI data to be made available in FITS files for common events. CHIANTI: Landi to include higher n transitions (Sylwester J. suggestion), Urnov, Mason NON-MAXWELLIANS: Dzifcakova, Mason, Sylwester J., Chifor Results of working groups to be posted on the workshop's website. RETURN |
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