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The X-ray luminosity of rotation-powered neutron stars

W. Becker·J. Trümper
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Abstract

As a result of recent observations with ROSAT and ASCA the number of rotation-powered pulsars seen at X-ray energies has increased substantially. In this paper we review the phenomenology of the observed X-ray emission properties. At present 27 pulsars are detected, representing a wide range of ages (10^3 - 7 x 10^9 yrs), magnetic field strength (10^8 - 10^13 G) and spin periods (1.6 - 530 ms). Despite these dispersions in parameters all pulsars show an X-ray luminosity closely correlated with the rotational energy loss. This suggests that most of the observed X-rays are produced by magnetospheric emission originating from the co-rotating magnetosphere. Only for three middle aged pulsars (PSR 0656+14, Geminga and PSR 1055-52) and probably for the Vela-pulsar an additional thermal component is detected which can be attributed to thermal emission from the neutron stellar surface.

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W. Becker, J. Trümper. 1997-08-19. The X-ray luminosity of rotation-powered neutron stars. https://arxiv.org/abs/astro-ph/9708169

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