Sizes of flaring kernels in various parts of the Hα line profile

Abstract. In this paper we present new results of spectra-photometrical investigations of the flaring kernels' sizes and their intensities measured simultaneously in various parts of the Hα line profile. Our investigations were based on the very high temporal resolution spectral-imaging observations of the solar flares collected with Large Coronagraph (LC), Multi-channel Subtractive Double Pass Spectrograph and Solar Eclipse Coronal Imaging System (MSDP-SECIS) at Białkow Observatory (University of Wrocław, Poland).

We have found that the areas of the investigated individual flaring kernels vary in time and in wavelengths, as well as the intensities and areas of the Hα flaring kernels decreased systematically when observed in consecutive wavelengths toward the wings of the Hα line. Our result could be explained as an effect of the cone-shaped lower parts of the magnetic loops channeling high energy particle beams exciting chromospheric plasma.