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Asymmetric X-ray Pulsar Beam Emission

Published online by Cambridge University Press:  25 April 2016

Whayne E. P. Padden
Affiliation:
Department of Theoretical Physics, University of Sydney
Michelle C. Storey
Affiliation:
Department of Theoretical Physics, University of Sydney

Abstract

Many of the X-ray pulsars for which X-ray lightcurves have been presented in the literature exhibit asymmetric emission beams. We postulate the existence of an off-centre magnetic dipole field embedded in the rotating neutron star and show that such a field leads to varying rates of matter transfer between an accretion dise and the neutron star surface, over a rotation period. Assuming that the accretion rate onto the surface is simply related to the luminosity, we show that most of the observed asymmetries can be accounted for by this mechanism.

Type
Contributions
Copyright
Copyright © Astronomical Society of Australia 1985

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