X-RAY ENHANCEMENT AND LONG-TERM EVOLUTION OF SWIFT J1822.3-1606

作者：Benli Onur^*; Caliskan S; Ertan U; Alpar M A; Truemper J E; Kylafis N D

来源：Astrophysical Journal, 2013, 778(2): 119.

DOI：10.1088/0004-637X/778/2/119

• accretion, accretion disks
• pulsars: individual (AXPs)
• stars: neutron
• X-rays: bursts

We investigate the X-ray enhancement and the long-term evolution of the recently discovered second %26quot;low-B magnetar%26quot; Swift J1822.3-1606 in the frame of the fallback disk model. During a soft gamma burst episode, the inner disk matter is pushed back to larger radii, forming a density gradient at the inner disk. Subsequent relaxation of the inner disk could account for the observed X-ray enhancement light curve of Swift J1822.3-1606. We obtain model fits to the X-ray data with basic disk parameters similar to those employed to explain the X-ray outburst light curves of other anomalous X-ray pulsars and soft gamma repeaters. The long period (8.4 s) of the neutron star can be reached by the effect of the disk torques in the long-term accretion phase ((1-3) x 10(5) yr). The currently ongoing X-ray enhancement could be due to a transient accretion epoch, or the source could still be in the accretion phase in quiescence. Considering these different possibilities, we determine the model curves that could represent the long-term rotational and the X-ray luminosity evolution of Swift J1822.3-1606, which constrain the strength of the magnetic dipole field to the range of (1-2) x 10(12) G on the surface of the neutron star.

• 出版日期2013-12-1