New Results on the Early-type Close Binary CV Velorum

Abstract

Introduction : This study aims at improving the fundamental parameters of the massive close double-lined eclipsing binary CV Velorum. Methods: We gathered new high-resolution echelle spectroscopy on 13 consecutive nights, hence covering almost two full orbits. These data were analysed and provided the spectroscopic orbital parameters from various spectral lines. We computed a simultaneous solution to all the available radial-velocity and light data. Results: We obtained new and more accurate values for the physical parameters We also discovered low-amplitude periodic line-profile variations for both components. These occur with the orbital period, pointing towards an extrinsic origin rather than oscillations. Finally, we show that the primary rotates sub-synchronously while the secondary's v sin i is compatible with synchronous rotation. Conclusion: The very precise fundamental parameters derived for CV Vel, with uncertainties less than 1%, constitute a fruitful observational test for any fine-tuning of stellar evolution models of intermediate-mass B stars