1 / 12

Analysis of Potassium Abundance in Selected Solar Flares

Analysis of Potassium Abundance in Selected Solar Flares. J. Sylwester , B. Sylwester (SRC, Poland) K.J.H . Phillips (GSFC, USA) J.L. Culhane (MSSL, UK) C. Brown (NRL, USA), J. Lang (RAL, UK) A.I. Stepanov (IZMIRAN, Russia). RESIK - instant collection of spectra.

harlow
Download Presentation

Analysis of Potassium Abundance in Selected Solar Flares

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Analysis of Potassium Abundance in Selected Solar Flares J. Sylwester, B. Sylwester (SRC, Poland) K.J.H. Phillips (GSFC, USA) J.L. Culhane (MSSL, UK) C. Brown (NRL, USA), J. Lang (RAL, UK) A.I. Stepanov (IZMIRAN, Russia) 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  2. RESIK - instant collection of spectra Bragg law: kλ=2d sinΘ РентгеновскийСпектрометрсИзогнутымиКристаллами Measure spectra in range: 0.335 nm – 0.610 nm, instantly in all λ 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  3. Well callibrated RESIK, RHESSI, and GOES Spectra: 2003 April 26 flare Brian Dennis & Ken Phillips 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  4. Some example spectra from ~1000 reformatted 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  5. Prompt analysis - isothermal approximation - T & EM #4 T from #1/#4 flux ratio EM from T and #4 flux (CHIANTI atomic data) Dividing the photon flux by EM  spectrum per unit EM (1044 cm-3) Group spectra according to T and take averages #1 Continuum from T and EM Removing the continuum allows to study line fuxes 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  6. Vicinity of K and Ar He-like triplets Lines + cont Lines Lines + cont Lines G ratio G ratio Ar K 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  7. Observed temperature dependence for K XVIII w Line Flux above the continuum (area) divide by emission measure determined in the isothermal approximation AK x 2 Excitation: Mewe Ion equil: Mazzotta AK / 2 Polynomial fit AK = 6.31 10-7 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  8. Observed temperature dependence for ArXVII w(S XV 1s2 – 1s6p contribution removed) Line Flux above the continuum (area) divide by emission measure determined in the isothermal approximation Excitation: Mewe Ion equil: Mazzotta AAr x 1.4 AAr x 2/3 Polynomial fit 1/5 AAr = 5.62 10-6 Nearly perfect overlapping of the best fit with the theoretical dependence 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  9. Differences „by eye” AK < 1/3 average : 8 intense cases AK > 1.8 x average : 8 intense cases Similar T ~ 7 MK 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  10. relative line variability - T plots 4 K Ar FWHM= x 2.2 FWHM= x 3.6 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  11. Does K/Ar ratio correlate with… NO ! NO ! M C 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

  12. Conclusions • Regular temperature behaviour of line emissivities experimentaldetermination of emission functions (be aware of assumptions!) • Variation in AK by factor of at least ~ 6 • Scatter around the average due to: • Possible abundance variations • Multi-temperature plasma (DEM) • Preferential ‘tail’ contribution to lines • Precise variations in AK can be studied only together with DEM  accuracy of ~5% in absolute values for a particular spectrum. 35th COSPAR Scientific Commission E1.9 Paris, 18-25 July 2004

More Related