The nature of the line profile variability in the spectrum of the massive binary HD 152219H. Sana
European Southern Observatory, Alonso de Cordova 3107, Vitacura, Santiago 19, Chile
Received 27 May 2008 / Accepted 21 March 2009
Context. HD 152219 is a massive binary system with O9.5 III + B1-2 V/III components and a short orbital period of 4.2 d. Its primary component further displays clear line profile variability (LPV). The primary component being located within the pulsational instability domain predicted for high-luminosity stars, we previously suggested that the observed LPV could be associated with non-radial pulsations.
Aims. The aim of the present work is to determine the nature of the observed LPV in the spectrum of the primary component of HD 152219.
Methods. During a 4-night FEROS monitoring campaign, we collected a new set of 134 high signal-to-noise spectra. These new observations were then used to re-investigate the variability of different line profiles in the spectrum of HD 152219.
Results. Based on the present analysis, we discard the non-radial pulsations and point out the Rossiter-McLaughlin effect as the cause of the LPV in HD 152219. The upper limit on the amplitude of possible weak pulsations is set at a few parts per thousand of the continuum level.
Key words: stars: individual: HD 152219 -- stars: oscillations -- binaries: close -- binaries: spectroscopic -- stars: early-type -- line: profiles
© ESO 2009