Physical Sciences and Mathematics Commons^™

Time-Series Photometric Spot Modeling. Ii. Fifteen Years Of Photometry Of The Bright Rs Cvn Binary Hr 7275., Klaus G. Strassmeier, Douglas S. Hall, Gregory W. Henry

Information Systems and Engineering Management Research Publications

We present a time-dependent spot modeling analysis of 15 consecutive years of V-band photometry of the long-period (Porb = 28.6 days) RS CVn binary HR 7275. This baseline in time is one of the longest, uninterrupted intervals a spotted star has been observed. The spot modeling analysis yields a total of 20 different spots throughout the time span of our observations. The distribution of the observed spot migration rates is consistent with solar-type differential rotation and suggests a lower limit of the differential-rotation coefficient of 0.022 +/-0.004. The observed, maximum lifetime of a single spot (or spot group) is 4.5 …