A Pulsar-atmosphere Model for Psr 0656+14
نویسندگان
چکیده
We present a pulsar-atmosphere (PA) model for modulated thermal X-ray emission from cooling magnetized neutron stars. The model synthesizes the spectral properties of detailed stellar atmosphere calculations with the non-uniform surface properties anticipated for isolated, aging radio pulsars, and general relativistic effects on photon trajectories. We analyze the archival Chandra observations of the middle-aged radio pulsar PSR 0656+14 with the PA model and find it is an excellent representation of the phase-averaged X-ray spectrum for a broad range of polar effective temperature Tp and column density NH ≃ 10 20 cm. The spectral fits favor a subsolar neutron star mass M . 1.0 M⊙, a large radius R = 15 − 16 km for a source distance d ≃ 190 pc, while retaining consistency with theoretical neutron star equations-of-state. The modulated spectrum constrains the angular displacement of the pulsar spin axis to 30± 2 with respect to the line of sight.
منابع مشابه
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