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

H. Quaintrell, A. J. Norton, T. D. C. Ash +5

We report new radial velocity observations of GP Vel/HD77581, the optical companion to the eclipsing X-ray pulsar Vela X-1. Using data spanning more than two complete orbits of the…