Time-Varying Thermal Emission in Solar Flares.

Autor: Jain, R., Rajpurohit, A. S., Aggarwal, M., Jamwal, R., Awasthi, A.
Zdroj: Magnetic Coupling Between the Interior & Atmosphere of the Sun; 2010, p465-470, 6p
Abstrakt: We study thermal emission in solar flares using high-resolution X-ray spectra obtained with the Si detector of the Solar X-ray Spectrometer (SOXS) mission onboard the GSAT-2 Indian spacecraft launched in 2003. We model the spectral-temporal evolution of the medium-hard X-ray flux in terms of an evolving multi-temperature plasma governed by thermal conduction cooling and find agreement with the observations. By measuring the DEM power-law index for five M-class flares, we find that the emission in the 6–20 keV energy range is dominated by temperatures 15–50MK, while the power-law index of the thermal spectrum varies over 2.2–6.1. The mean value of the thermal conduction cooling time is 1,440 s; the temperature-dependent cooling time varies from 22 to 102 s. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index