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The Anomalous X-ray Pulsars

S. Mereghetti·L. Chiarlone·G. L. Israel·L. Stella
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Abstract

The Anomalous X-ray Pulsars (AXPs) are a small class of pulsars with spin periods in the 6-12 s range, very soft X-ray spectra, secular spin down on time scales of ~10^3-10^5 years, and lack of bright optical counterparts. Two, possibly three, of them are close to the centre of shell-like supernova remnants. AXPs are one of the most enigmatic classes of galactic high-energy sources. Isolated neutron stars powered by the loss of rotational energy can be excluded on energetic grounds. The models based on neutron stars involve either accretion (perhaps from a fossil disk around an isolated neutron star) or the decay of a very strong magnetic field (10^14-10^15 G). We review the models and the observational properties of AXPs, including recent XMM-Newton and Chandra observations. We also present some unpublished ASCA data.

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S. Mereghetti, L. Chiarlone, G. L. Israel, L. Stella. 2002-05-08. The Anomalous X-ray Pulsars. https://arxiv.org/abs/astro-ph/0205122

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