Multicolour time series photometry of the T Tauri star CVSO 30

Abstract

Five consecutive runs of at least five hours, and two shorter runs, of V(RI)C time series photometry of CVSO 30 are presented. No evidence could be seen for planetary transits, previously claimed in the literature for this star. The photometry described in this paper, as well as earlier observations, can be modelled by two non-sinusoidal periodicities of 8 and 10.8 h (frequencies 3 and 2.23 d−1) or their 1 d−1 aliases. The possibility is discussed that star-spots at different latitudes of a differentially rotating star is responsible for the brightness modulations. The steep wavelength dependence of the variability amplitudes is best described by hot star-spots.