Magnetic activity and spectral behavior of RS CVn binary system (IM Pegasi) in the ultraviolet
摘要
We present observations from the International Ultraviolet Explorer (IUE) covering the period from 1981 to 1992 of the long-period single-lined RS Canum Venaticorum (RS CVn) binary star, IM Pegasi, to elucidate the spectral behavior and physical conditions within its atmosphere. The ultraviolet observations reveal signs of flare activity occurring in the chromosphere and transition region of the primary star. In addition to the flaring activity, the emission lines exhibit a spectrum of variations categorized as high, intermediate, and low. The relation between line fluxes and orbital phases has been established. The flaring activity was notably observed in 1985. The reddening of IM Pegasi was assessed using the 2200 Å absorption feature, yielding an estimate of E (B-V) = 0. The average mass loss rate is calculated to be approximately 1.2 × 10− 10 M