Zonal Model of Starspots. Application to RS CVn Systems

Abstract

Model results on starspots in 15 chromospherically active type RS CVn binary systems are presented. The dependences of the parameters of the spots on the principal characteristics of the stars (spectral class, luminosity class, rotation, Rossby number) are examined. Latitudinal drift of the spots, cycles in the spot activity, and differential rotation are found in 9 of the stars.

Astrophysics in 2005

“…"Active longitudes" is the idea that spots, excess magnetic flux, and chromospheric emission may tend to pop out at the same place repeatedly over very long periods of time (e.g., Alekseev & Kozhevnikova 2005 on LQ Hya, a single dMe star). The behavior of K 1 Ceti (Rucinski et al 2004) may mean that both an active longitude and the pattern of differential rotation have been stable for 30 years.…”

Chemical Composition of the RS CVn-Type Star Lambda Andromedae

“…General properties of RS CVn systems are comprehensively described by Montesinos et al (1988). The photometric brightness variation analysis, Doppler imaging and spectral line analysis of RS CVn stars indicate that starspots may cover more than 20% of their surfaces (Rodonó et al 1995;Berdyugina et al 1998bBerdyugina et al , 2000Jeffers 2005;Alekseev & Kozhevnikova 2005). One of the largest filling factors (44%) was found for the RS CVn binary V841 Cen (Strassmeier et al 2008).…”