Coronal loops and pulsations of radiation from flare stars

1Stepanov, AV, 2Tsap, YT, 1Kopylova, Yu.G, 1Kupriyanova, EG
1Main Astronomical Observatory of the Russian Academy of Sciences, St. Petersburg, Russia
2Scientific-Research Institute «Crimean Astrophysical Observatory» of the Ministry for Education and Science of Ukraine, Nauchny, Crimea, Ukraine
Kosm. nauka tehnol. 2004, 10 ;(5-6):141-144
Publication Language: Russian
On the basis of the analogy between solar and stellar flares, the oscillations with periods of tens of seconds observed in the case of the EV Lac in the U and В bands are analyzed. We associated the pulsations of radiations with the fast magnetoacoustic oscillations of coronal arcs. The values of the magnetic field В ≈ 32 mT, temperature Т ≈ 3.7·10 К, and number density n ≈ 1.6·1011 cm3 in the region of the flare energy release are estimated. Some arguments in favour of localization of the optical radiation source at loop footpoints are obtained.
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