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Thermal emission from low-field neutron stars

B. T. Gaensicke·T. M. Braje·R. W. Romani
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Abstract

We present a new grid of LTE model atmospheres for weakly magnetic (B<=10e10G) neutron stars, using opacity and equation of state data from the OPAL project and employing a fully frequency- and angle-dependent radiation transfer. We discuss the differences from earlier models, including a comparison with a detailed NLTE calculation. We suggest heating of the outer layers of the neutron star atmosphere as an explanation for the featureless X-ray spectra of RX J1856.5-3754 and RX J0720.4-3125 recently observed with Chandra and XMM.

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B. T. Gaensicke, T. M. Braje, R. W. Romani. 2002-03-04. Thermal emission from low-field neutron stars. https://doi.org/10.1051/0004-6361%3A20020332

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