Broad-band X-ray spectra of anomalous X-ray pulsars and soft. gamma-ray repeaters: pulsars in a weak-accretion regime?

作者：Zezas A^*; Truemper J E; Kylafis N D

来源：Monthly Notices of the Royal Astronomical Society, 2015, 454(4): 3366-3375.

DOI：10.1093/mnras/stv1918

• accretion, accretion discs
• pulsars: individual: 4U 0142+61
• pulsars: individual: 1E 1547-5408
• pulsars: individual: 4U 0142+61
• pulsars: individual: 1RXS J1708-4009
• pulsars: individual: SGR 1900+14

We present the results from the analysis of the broad-band X-ray spectra of five anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs). We fit their Suzaku and INTEGRAL spectra with models appropriate for the X-ray emission from the accretion flow on to a pulsar. We find that their X-ray spectra can be well described with this model. In particular, we find that (a) the radius of the accretion column is similar to 150-350 m resulting in a transverse optical depth of similar to 1, (b) the vertical Thompson optical depth is approximate to 50-400, and (c) their luminosity translates in accretion rates approximate to 10(15) g s(-1). These results are in good agreement with the predictions from the fall-back disc model, providing further support in the interpretation of AXPs and SGRs as accreting pulsars.

• 出版日期2015-12-21