The mass of the neutron star in Vela X-1 and tidally induced non-radial oscillations in GP Vel

@article{Quaintrell2003TheMO,
  title={The mass of the neutron star in Vela X-1 and tidally induced non-radial oscillations in GP Vel},
  author={Hannah Quaintrell and Andrew J. Norton and T. D. C. Ash and Paul Roche and Bart Willems and Timothy R. Bedding and Ivan K. Baldry and Radboud University and UK. and Kildrummy Technologies Ltd and University of Glamorgan and University of Leicester and University of Western Sydney and Australia. and Johns Hopkins University and Usa and Anton Pannekoek Institute and The Netherlands.},
  journal={Astronomy and Astrophysics},
  year={2003},
  volume={401},
  pages={313-323}
}
We report new radial velocity observations of GP Vel / HD 77581, the optical companion to the eclipsing X-ray pulsar Vela X-1. Using data spanning more than two complete orbits of the system, we detect evidence for tidally induced non- radial oscillations on the surface of GP Vel, apparent as peaks in the power spectrum of the residuals to the radial velocity curve fit. By removing the effect of these oscillations (to first order) and binning the radial velocities, we have determined the semi… 

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