caa a22 4500 445346337 CHVBK 20180317142830.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s11207-011-9812-8 doi (NATIONALLICENCE)springer-10.1007/s11207-011-9812-8 Determination of Electron Density and Filling Factor for Soft X-Ray Flare Kernels [Elektronische Daten] [J. Jakimiec, U. Ba̧k-Stȩślicka] In the standard method of electron density determination for soft X-ray (SXR) flare kernels, it is necessary to assume what the extent is of a kernel along the line of sight. This is a source of significant uncertainty of the obtained densities. In our previous paper (Ba̧k-Stȩślicka and Jakimiec, Solar Phys. 231, 95, 2005) we have proposed a new method of deriving electron density, in which it is not necessary to assume what the extent of a kernel along the line of sight is. This new method is based on the idea that many flares, during their decay phase, can be described with a sequence of steady-state models [quasi-steady-state (QSS) evolution] and then a scaling law, derived for steady-state models, can be used to determine the electron density. The aim of the present paper is: i) to improve both methods of density determination, and ii) to compare the densities obtained with the two methods. We have selected a number of flares which showed QSS evolution during their decay phase. For these flares the electron density, N, has been derived by means of both the standard method and with our QSS method. Comparison of the N values obtained with the two different methods allowed us: i) to test the obtained densities, ii) to evaluate the volume filling factor of the SXR emitting plasma. Generally, we have found good agreement (no large systematic differences) between the values of electron density obtained with the two methods, though for some cases the values differed by up to a factor of two. For most flare kernels the filling factor turned out to be about one near the flare maximum. The Author(s), 2011 Sun: corona nationallicence Flares nationallicence X-rays nationallicence Jakimiec J. Astronomical Institute, University of Wrocław, ul. Kopernika 11, 51-622, Wrocław, Poland aut Ba̧k-Stȩślicka U. Astronomical Institute, University of Wrocław, ul. Kopernika 11, 51-622, Wrocław, Poland aut Solar Physics Springer Netherlands 272/1(2011-08-01), 91-100 0038-0938 272:1<91 2011 272 11207 https://doi.org/10.1007/s11207-011-9812-8 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11207-011-9812-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jakimiec J. Astronomical Institute, University of Wrocław, ul. Kopernika 11, 51-622, Wrocław, Poland aut NATIONALLICENCE 700 1- Ba̧k-Stȩślicka U. Astronomical Institute, University of Wrocław, ul. Kopernika 11, 51-622, Wrocław, Poland aut NATIONALLICENCE 773 0- Solar Physics Springer Netherlands 272/1(2011-08-01), 91-100 0038-0938 272:1<91 2011 272 11207 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer