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X-ray Radiation from the Millisecond Pulsar J0437-4715

V. E. Zavlin·G. G. Pavlov·D. Sanwal·R. N. Manchester·J. Truemper·J. P. Halpern·W. Becker
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Abstract

We report on spectral and timing observations of the nearest millisecond pulsar J0437-4715 with Chandra. The pulsar spectrum, detected up to 7 keV, cannot be described by a simple one-component model. We suggest that it consists of two components, a nonthermal power-law spectrum generated in the pulsar magnetosphere, with a photon index about 2, and a thermal spectrum emitted by heated polar caps, with a temperature decreasing outwards from 2 MK to 0.5 MK. The lack of spectral features in the thermal component suggests that the neutron star surface is covered by a hydrogen (or helium) atmosphere. The timing analysis shows one X-ray pulse per period, with a pulsed fraction of about 40% and the peak at the same pulse phase as the radio peak. No synchrotron pulsar-wind nebula is seen in the X-rays.

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V. E. Zavlin, G. G. Pavlov, D. Sanwal, R. N. Manchester, J. Truemper, J. P. Halpern, W. Becker. 2001-12-26. X-ray Radiation from the Millisecond Pulsar J0437-4715. https://doi.org/10.1086/339351

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