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arXiv · 1103.0955

Modelling lightcurves and spectra of transient Anomalous X-ray Pulsars

S. Zane·A. Albano·R. Turolla·G. L. Israel·L. Nobili·L. Stella
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Abstract

We present the first detailed joint modelling of both the timing and spectral properties during the outburst decay of transient anomalous X-ray pulsars. We consider the two sources XTE J1810-197 and CXOU J164710.2-455216, and describe the source decline in the framework of a twisted magnetosphere model, using Monte Carlo simulations of magnetospheric scattering and mimicking localized heat deposition at the NS surface following the activity. Our results support a picture in which a limited portion of the star surface close to one of the magnetic poles is heated at the outburst onset. The subsequent evolution is driven both by the cooling/varying size of the heated cap and by a progressive untwisting of the magnetosphere.

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S. Zane, A. Albano, R. Turolla, G. L. Israel, L. Nobili, L. Stella. 2011-03-04. Modelling lightcurves and spectra of transient Anomalous X-ray Pulsars. https://doi.org/10.1063/1.3629501

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