Modeling the Non-Thermal X-ray Tail Emission of Anomalous X-ray Pulsars
The paradigm for Anomalous X-ray Pulsars (AXPs) has evolved recently with the discovery by INTEGRAL and RXTE of flat, hard X-ray components in three AXPs. These non-thermal spectral components differ dramatically from the steeper quasi-power-law tails seen in the classic X-ray band in these sources, and can naturally be attributed to activity in the magnetosphere. Resonant, magnetic Compton upscattering is a candidate mechanism for generating this new component, since it is very efficient in the strong fields present near AXP surfaces. In this paper, results from an inner magnetospheric model for upscattering of surface thermal X-rays in AXPs are presented, using a kinetic equation formalism and employing a QED magnetic scattering cross section. Characteristically flat and strongly-polarized emission spectra are produced by non-thermal electrons injected in the emission region. Spectral results depend strongly on the observers orientation and the magnetospheric locale of the scattering, which couple directly to the angular distributions of photons sampled. Constraints imposed by the Comptel upper bounds for these AXPs are mentioned.
non-thermal radiation mechanisms magnetic fields neutron stars pulsars X-rays
Matthew G. Baring Alice K. Harding
Department of Physics and Astronomy, MS 108, Rice University, MS 108, 6100 Main St., Houston, TX 770 Gravitational Astrophysics Laboratory, NASA Goddard Space Flight Center, Code 663, Greenbelt, MD 207
国际会议
紧凑型物体的天体物理学国际会议(International Conference on Astrophysics of Compact Objects)
安徽黄山
英文
93-100
2007-07-01（万方平台首次上网日期，不代表论文的发表时间）