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Low-Energy X-ray Emission from Young Isolated Neutron Stars

M. Ruderman
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Abstract

A young neutron star with large spin-down power is expected to be closely surrounded by an e+/- pair plasma maintained by the conversion of gamma-rays associated with the star's polar-cap and/or outer-gap accelerators. Cyclotron-resonance scattering by the e- and e+ within several radii of such neutron stars prevents direct observations of thermal X-rays from the stellar surface. Estimates are presented for the parameters of the Planck-like X-radiation which ultimately diffuses out through this region. Comparisons with observations, especially of apparent blackbody emission areas as a function of neutron star age, support the proposition that we are learning about a neutron star's magnetosphere rather than about its surface from observations of young neutron star thermal X-rays.

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M. Ruderman. 2003-10-28. Low-Energy X-ray Emission from Young Isolated Neutron Stars. https://arxiv.org/abs/astro-ph/0310777

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