DOPPLER IMAGING STARS WITH MODERATE ROTATION - THE SPOT DISTRIBUTION ON SIGMA GEMINORUM

It is demonstrated that the Doppler imaging technique is capable of re covering the cool spot distributions on stars rotating as slowly as 15 km s-1. The technique is employed to derive the spot distribution on the RS CVn star sigma Gem (v sin i = 27 km s-1). The spot distribution on this star consists of five spots which are in a band centered near latitude +55-degrees and which may be indicative of an active latitud e band. Although sigma Gem exhibits high-latitude spot activity, it sh ows no evidence for a polar spot like those seen on virtually every ot her RS CVn star. The different spot morphology of sigma Gem may be due to the long period of the star.