Long-term evolution of anomalous x-ray pulsars and soft gamma repeaters

Benli, Onur and Ertan, Ünal (2016) Long-term evolution of anomalous x-ray pulsars and soft gamma repeaters. Monthly Notices of the Royal Astronomical Society, 457 (4). pp. 4114-4122. ISSN 0035-8711 (Print) 1365-2966 (Online)

This is the latest version of this item.

Full text not available from this repository. (Request a copy)

Abstract

We have investigated the long-term evolution of individual anomalous X-ray pulsars (AXPs) and soft gamma repeaters (SGRs) with relatively well constrained X-ray luminosity and rotational properties. In the frame of the fallback disc model, we have obtained the ranges of disc mass and dipole field strength that can produce the observed source properties. We have compared our results with those obtained earlier for dim isolated neutron stars (XDINs). Our results show that (1) the X-ray luminosity, period and period derivative of the individual AXP/SGR sources can be produced self-consistently in the fallback disc model with very similar basic disc parameters to those used earlier in the same model to explain the long-term evolution of XDINs, (2) except two sources, AXP/SGRs are evolving in the accretion phase; these two exceptional sources, like XDINs, completed their accretion phase in the past and are now evolving in the final propeller phase and still slowing down with the disc torques, (3) the dipole field strengths (at the poles) of XDINs are in the 10(11)-10(12) G range, while AXP/SGRs have relatively strong dipole fields between 1 and 6 x 10(12) G, and (4) the source properties can be obtained with large ranges of disc masses which do not allow a clear test of correlation between disc masses and the magnetic dipole fields for the whole AXP/SGRs and XDIN population.
Item Type: Article
Uncontrolled Keywords: accretion, accretion discs; stars: magnetars; stars: neutron; pulsars: individual: AXPs; pulsars: individual: SGRs
Subjects: Q Science > QB Astronomy > QB460-466 Astrophysics
Q Science > QC Physics
Divisions: Faculty of Engineering and Natural Sciences > Basic Sciences > Physics
Faculty of Engineering and Natural Sciences
Depositing User: Ünal Ertan
Date Deposited: 11 Nov 2016 16:06
Last Modified: 11 Nov 2016 16:06
URI: https://research.sabanciuniv.edu/id/eprint/30067

Available Versions of this Item

Actions (login required)

View Item
View Item