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Neutron stars in X-ray pulsars and their magnetic fields

S. B. Popov·V. M. Lipunov
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Abstract

Estimates of the magnetic field of neutron stars in X-ray pulsars are obtained using the hypothesis of the equilibrium period for disk and wind accretion and also from the BATSE data on timing of X-ray pulsars using the observed maximum spin-down rate. Cyclotron lines at energies $\ge 100$ keV in several Be-transient are predicted for future observations. We suggest a new method of estimating distances to X-ray pulsars and their magnetic fields. Using observations of fluxes and period variations in the model of disk accretion one can estimate the magnetic momentum of a neutron star and the distance to X-ray pulsar. As an illustration the method is applied to the system GROJ1008-57.

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S. B. Popov, V. M. Lipunov. 1999-12-29. Neutron stars in X-ray pulsars and their magnetic fields. https://arxiv.org/abs/astro-ph/9912545

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