Institut national de recherche scientifique français Univerité Pierre et Marie Curie Université Paris Diderot - Paris 7

Rapidly rotating late B-type stars : spots or pulsations ?

vendredi 15 février 2013, par Pieter Degroote (KU Leuven & Aarhus University)

Recent space based photometry (CoRoT & MOST) delivered a few late B-type stars, where the variability shows intriguing similarity with the light curves of cool, differentially rotating spotted stars. A pilot study (Degroote et al., 2009) showed that it is possible to explain both the light curve variability and the spectral line profiles with a differentially rotating spot model. However, white light photometry alone is not sufficient to disentangle variability due to spots or pulsations. Much effort is devoted to building models that can explain all of the observations simultaneously in one consistent model, a method which we have generalised also to binary and multiple stars, and other types of observations. After the pilot study, more targets were looked for and found. The multicolour spaced based photometry and ground based spectroscopy available for some of these targets allow for a follow-up study to explain the observations and understand these objects.