Lithium Abundance and Activity for 57 Rs Cvn Systems

Quiescent and Flaring Structure in Rs Cvn

VLA multifrequency observations of RS CVn binaries

We present multiepoch Very Large Array (VLA) observations at 1.4 GHz, 4.9 GHz, 8.5 GHz and 14.9 GHz for a sample of eight RS CVn binary systems. Circular polarization measurements of these systems are also reported. Most of the fluxes observed are consistent with incoherent emission from mildly relativistic electrons. Several systems show an increase of the degree of circular polarization with ...

A NON-EMPIRICAL ROTATION-ACTIVITY RELATION FOR RS CVn BINARIES USING RADIO LUMINOSITIES

An analysis of a comprehensive survey of radio luminosities for RS CVn binary systems is given. A comparison is made between the rotation-activity correlations found using the usual semi-empirical Rossby number and a Rossby number deduced from detailed convection zone models. The use of a non-empirically derived Rossby number does not signiicantly improve the rotation-activity correlation. Alth...

Letter to the Editor Permanent active longitudes and activity cycles on RS CVn stars

A new analysis of the published long-term photometric observations has revealed permanent active-longitude structures in four RS CVn stars: EI Eri, II Peg, σ Gem, and HR 7275. Two active longitudes separated by half of the period are found to dominate on the surface during all available seasons. The positions of the longitudes on three stars (EI Eri, II Peg, HR 7275) are migrating in the orbita...

A Study of the Coronal Plasma in RS CVn binary systems : HR 1099 and co

XMM-Newton has been performing comprehensive studies of X-ray luminous RS CVn binary systems in its calibration and guaranteed time programs. We present results from ongoing investigations in the context of a systematic study of coronal emission from RS CVns. We concentrate here on coronal abundances and investigate the abundance pattern in RS CVn binaries as a function of activity and average ...