Modelling lightcurves and spectra of transient Anomalous X-ray Pulsars
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.
- Publication:
-
AstroPhysics of Neutron Stars 2010: A Conference in Honor of M. Ali Alpar
- Pub Date:
- September 2011
- DOI:
- 10.1063/1.3629501
- arXiv:
- arXiv:1103.0955
- Bibcode:
- 2011AIPC.1379..140Z
- Keywords:
-
- spectral analysis;
- corona;
- stellar evolution;
- Monte Carlo methods;
- 97.10.Ri;
- 97.10.Ex;
- 97.10.Cv;
- 02.70.Uu;
- Luminosities;
- magnitudes;
- effective temperatures colors and spectral classification;
- Stellar atmospheres;
- radiative transfer;
- opacity and line formation;
- Stellar structure interiors evolution nucleosynthesis ages;
- Applications of Monte Carlo methods;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 4 Pages, 7 Figures. To be published in the proceedings of "Astrophysics of Neutron Stars 2010", 1-5 August 2010, Cesme, Turkey, AIP Conference Proceedings