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The distance and radius of the neutron star PSR B0656+14

W. F. Brisken·S. E. Thorsett·A. Golden·W. M. Goss
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Abstract

We present the result of astrometric observations of the radio pulsar PSR B0656+14, made using the Very Long Baseline Array. The parallax of the pulsar is pi = 3.47 +- 0.36 mas, yielding a distance of 288 +33 -27 pc. This independent distance estimate has been used to constrain existing models of thermal x-ray emission from the neutron star's photosphere. Simple blackbody fits to the x-ray data formally yield a neutron star radius R_inf ~ 7-8.5 km. With more realistic fits to a magnetized hydrogen atmosphere, any radius between ~13 and ~20 km is allowed.

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W. F. Brisken, S. E. Thorsett, A. Golden, W. M. Goss. 2003-06-11. The distance and radius of the neutron star PSR B0656+14. https://doi.org/10.1086/378184

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