We demonstrate the power of the local correlation tracking technique on stellar data for the first time. We recover the spot migration pattern of the long-period RS CVn-type binary σ Gem from a set of six Doppler images from 3.6 consecutive rotation cycles. The resulting surface flow map suggests a weak anti-solar differential rotation with α≈−0.0022±0.0016, and a coherent poleward spot migration with an average velocity of 220±10 m s−1. This result agrees with our recent findings from another study and could also be confirmed theoretically.
@article{arxiv.0711.0771,
title = {Surface velocity network with anti-solar differential rotation on the active K-giant $\sigma$ Geminorum},
author = {Zs. Kõvári and J. Bartus and M. Švanda and K. Vida and K. G. Strassmeier and K. Oláh and E. Forgács-Dajka},
journal= {arXiv preprint arXiv:0711.0771},
year = {2009}
}
Comments
3 pages, 3 figures, conference title: 5th Potsdam Thinkshop, accepted for publication in Astronomische Nachrichten