Powering Anomalous X-ray Pulsars by Neutron Star Cooling
نویسندگان
چکیده
Using recently calculated analytic models for the thermal structure of ultramagnetized neutron stars, we estimate the thermal fluxes from young (t ∼ 1000 yr) ultramagnetized (B ∼ 10 G) cooling neutron stars. We find that the pulsed X-ray emission from objects such as 1E 1841-045 and 1E 2259+586 as well as many soft-gamma repeaters can be explained by photon cooling if the neutron star possesses a thin insulating envelope of matter of low atomic weight at densities ρ < 10 − 10 g/cm. The total mass of this insulating layer is M ∼ 10 − 10M⊙. Subject headings: stars: neutron — stars: magnetic fields — radiative transfer — X-rays: stars
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