MOST detects corotating bright spots on the mid-O-type giant ξ Persei

  title={MOST detects corotating bright spots on the mid-O-type giant $\xi$ Persei},
  author={Tahina Ramiaramanantsoa and Anthony F. J. Moffat and A. N. Chen'e and Noel D. Richardson and Huib F. Henrichs and S. Desforges and Victoria Antoci and Jason F. Rowe and Jaymie Matthews and Rainer Kuschnig and Werner W. Weiss and Dimitar D. Sasselov and Slavek M. Rucinski and David B. Guenther U. Montr'eal and Gemini Observatory and Universidad de Valpara'iso and Universidad de Concepci'on and University of Amsterdam and University of Aarhus and NASA-Ames and University of British Columbia and University of Vienna and Harvard-Smithsonian CfA and University of Toronto and U. SaintMary's},
  journal={Monthly Notices of the Royal Astronomical Society},
We have used the MOST (Microvariability and Oscillations of STars) microsatellite to obtain four weeks of contiguous high-precision broad-band visual photometry of the O7.5III(n)((f)) star ξ Persei in 2011 November. This star is well known from previous work to show prominent DACs (discrete absorption components) on time-scales of about 2 d from UV spectroscopy and non-radial pulsation with one (l = 3) p-mode oscillation with a period of 3.5 h from optical spectroscopy. Our MOST-orbit (101.4… Expand

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