On the nature of binary-system X-ray pulsars
Abstract
It is shown that the model of a rotating neutron star in the accretion phase gives a natural explanation of both long- and short-period X-ray pulsars in binary systems. Calculations show that a rotating neutron star can be braked to a period of tens of minutes and more in a time of less than one million years at a velocity of the stellar wind from the surface of the optical component of not less than about 10 billionths of a solar mass per year. Two alternatives are then possible: (1) the presently observed periods of pulsars are close to some equilibrium value determined by the magnitude of the magnetic field of the neutron star, its radius, and the rate of accretion onto it, or (2) the presently observed periods have a value much greater than the equilibrium value, so that only a monotonic increase of the rate of rotation should be observed. This last case occurs on the condition that the exit of O-B stars from the main sequence into the region of blue supergiants is accompanied by a thousand-fold increase of the mass outflow rate.
- Publication:
-
Soviet Astronomy Letters
- Pub Date:
- August 1976
- Bibcode:
- 1976SvAL....2..133L
- Keywords:
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- Binary Stars;
- Pulsars;
- Stellar Models;
- X Ray Sources;
- Astrophysics;
- Neutron Stars;
- Stellar Mass Ejection;
- Stellar Rotation;
- Astrophysics