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The Determination of the `Diffusion Coefficients' and the Stellar Wind Velocities for X-Ray Binaries

V. M. Lipunov·S. B. Popov
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Abstract

The distribution of neutron stars (NS's) is determined by stationary solution of the Fokker-Planck equation. In this work using the observed period changes for four systems: Vela X-1, GX 301-2, Her X-1 and Cen X-3 we determined D, the 'diffusion coefficient',-parameter from the Fokker-Planck equation. Using strong dependence of D on the velocity for Vela X-1 and GX 301-2, systems accreting from a stellar wind, we determined the stellar wind velocity. For different assumptions for a turbulent velocity we obtained $V=(660-1440) km s ^{-1}$. It is in good agreement with the stellar wind velocity determined by other methods. We also determined the specific characteristic time scales for the 'diffusion processes' in X-ray pulsars. It is of order of 200 sec for wind-fed pulsars and 1000-10000 sec for the disk accreting systems.

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V. M. Lipunov, S. B. Popov. 1995-04-20. The Determination of the `Diffusion Coefficients' and the Stellar Wind Velocities for X-Ray Binaries. https://doi.org/10.1080/10556799508203308

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