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arXiv · 1912.07984

A Multiwavelength Analysis of the Long-duration Flare Observed on 15 April 2002

A. Kepa·B. Sylwester·J. Sylwester·T. Mrozek·M. Siarkowski
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Abstract

We present a multiwavelength analysis of the long duration flare observed on 15 April 2002 (soft X-ray peak time at 03:55 UT, SOL2002-04-15T03:55). This flare occurred on the disk (S15W01) in NOAA 9906 and was observed by a number of space instruments including the Extreme-Ultraviolet Imaging Telescope on the Solar and Heliospheric Observatory (SOHO/EIT), the RESIK spectrometer onboard the Coronas-F spacecraft, and the Ramaty High Energy Solar Spectroscopic Imager (RHESSI). We have performed a complex analysis of these measurements and studied the morphology and physical parameters characterizing the conditions in flaring plasmas. The 195 A SOHO/EIT images have been used to study evolution of flaring loops. Analysis of RHESSI data provided the opportunity for a detailed analysis of hard X-ray emission with 1 keV energy resolution. We have used Geostationary Operational Environmental Satellite (GOES) observations for isothermal interpretation of the X-ray measurements. Temperature diagnostics of the flaring plasma have been carried out by means of a differential emission measure (DEM) analysis based on RESIK X-ray spectra.

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A. Kepa, B. Sylwester, J. Sylwester, T. Mrozek, M. Siarkowski. 2019-12-17. A Multiwavelength Analysis of the Long-duration Flare Observed on 15 April 2002. https://doi.org/10.1007/s11207-020-1581-9

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