Title: The Period Evolution of the Chemically Peculiar Star V473 Tau Author: Dogus Ozuyar, Ian R. Stevens
In this paper, the period evolution of the rotating chemically peculiar star V473 Tau (A0Si, V = 7.26 mag) is investigated. Even though the star has been observed for more than fifty years, for the first time four consecutive years of space-based data covering between 2007 and 2010 is presented. The data is from the STEREO satellite, and is combined with the archival results. The analysis shows that the rotation period of V473 Tau is 1.406829(10) days, and has slightly decreased with the variation rate of 0.11(3) s yr^-1 over time. Also, the acceleration timescale of the star is found to be around 11(63) x 10^6 yr, shorter than its main sequence lifetime (9.26(1.25) x 10^8 yr). This indicates that the process of decrease in period might be reversible. On this basis, it can be suggested that V473 Tau has a possible magnetic breaking and a differential rotation, which cause a variation in the movement of inertia, and hence the observed period change.