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X-ray Spectroscopy of Thermally Emitting Neutron Stars

M. H. van Kerkwijk
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Abstract

I describe recent high-resolution X-ray spectroscopy of surface emission from nearby, thermally emitting neutron stars. I focus on RX J0720.4-3125, RX J1308.6+2127, and RX J1605.3+3249, all of which have similar temperature, but differ in the presence and strength of absorption features in their spectra. I discuss possible causes for the absorption we see in two sources, and conclude that it may be proton cyclotron line absorption, but weakened due to the strong-field quantum electrodynamics effect of vacuum resonance mode conversion.

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M. H. van Kerkwijk. 2003-10-14. X-ray Spectroscopy of Thermally Emitting Neutron Stars. https://arxiv.org/abs/astro-ph/0310389

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