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arXiv · 2401.00117

AstroSat investigation of X-ray flares on two active K-M systems: CC Eri and AB Dor

Subhajeet Karmakar·Jeewan C. Pandey·Nikita Rawat·Gurpreet Singh·Riddhi Shedge
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Abstract

We present an X-ray and UV investigation of five X-ray flares detected on two active systems, CC Eri and AB Dor, using the AstroSat observatory. The peak X-ray luminosities of the flares in the 0.3$-$7.0 keV band are found to be within 10$^{31-33}$ erg s$^{-1}$. Preliminary spectral analysis indicates the presence of three and four-temperature corona for CC Eri and AB Dor, respectively, where the highest temperature is found to vary with flare. The flare temperatures peaked at 51$-$59 MK for CC Eri and 29$-$44 MK for AB Dor. The peak emission measures of the flaring loops are estimated to be $\sim$10$^{54}$ for CC Eri and $\sim$10$^{55}$ cm$^{-3}$ for AB Dor. Global metallic abundances were also found to increase during flares.

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Subhajeet Karmakar, Jeewan C. Pandey, Nikita Rawat, Gurpreet Singh, Riddhi Shedge. 2023-12-30. AstroSat investigation of X-ray flares on two active K-M systems: CC Eri and AB Dor. https://arxiv.org/abs/2401.00117

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