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XMM-Newton Observations of the Black Widow Pulsar PSR B1957+20

Hsiu-Hui Huang·Werner Becker
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Abstract

We report on XMM-Newton observations of the "Black Widow pulsar", PSR B1957+20. The pulsar's X-ray emission is non-thermal and best modeled with a single powerlaw spectrum of photon index 2.03(+0.51/-0.36). No coherent X-ray pulsations at the pulsar's spin-period could be detected, though a strong binary-phase dependence of the X-ray flux is observed for the first time. The data suggest that the majority of the pulsar's X-radiation is emitted from a small part of the binary orbit only. We identified this part as being near to where the radio eclipse takes place. This could mean that the X-rays from PSR B1957+20 are mostly due to intra-shock emission which is strongest when the pulsar wind interacts with the ablated material from the companion star.

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Hsiu-Hui Huang, Werner Becker. 2007-01-24. XMM-Newton Observations of the Black Widow Pulsar PSR B1957+20. https://arxiv.org/abs/astro-ph/0701611

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