Activity Correlations in Close Binary Systems

Abstract

The best way to learn about the detailed physical conditions associated with stellar activity is to construct detailed self-consistent model stellar atmospheres based on the wide range of diagnostics now available. A quicker rough analysis of the activity can be accomplished by studying the interrelations of the various diagnostics. Tight correlations between diagnostics suggest physical association, and the power law indices of the correlation can help to elucidate the general physical relation the diagnostics have with each other. Our aim in this study was to observe with the IUE satellite a homogeneous sample of stars for which there is extensive coronal data. The X-ray studies of close binaries by Walter and Bowyer (1981) and Walter (1982) provided such a sample; these stars are also accessible to the IUE because of their tendency to strong activity. Because of intrinsic stellar variability, this type of study is best carried out when all diagnostics are measured simultaneously. We have come fairly close to this ideal; only the coronal data is non-contemporaneous for most of the sample. Our reduction of the IUE data is quite similar to that of Ayres, Marstad and Linsky (1981, hereafter AML) and we have used essentially the same diagnostics.