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PSR J1740-3052 - a pulsar with a massive companion

I. H. Stairs·R. N. Manchester·A. G. Lyne·V. M. Kaspi·F. Camilo·J. F. Bell·N. D'Amico·M. Kramer·F. Crawford·D. J. Morris·A. Possenti·N. P. F. McKay·S. L. Lumsden·L. E. Tacconi-Garman·R. D. Cannon·N. C. Hambly·P. R. Wood
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Abstract

We report on the discovery of a binary pulsar, PSR J1740-3052, during the Parkes multibeam survey. Timing observations of the 570-ms pulsar at Jodrell Bank and Parkes show that it is young, with a characteristic age of 350 kyr, and is in a 231-day, highly eccentric orbit with a companion whose mass exceeds 11 M_sun. An accurate position for the pulsar was obtained using the Australia Telescope Compact Array. Near-infrared 2.2-um observations make with the telescopes at the Siding Spring observatory reveal a late-type star coincident with the pulsar position. However, we do not believe that this star is the pulsar's companion, because a typical star of this spectral type and required mass would extend beyond the pulsar's orbit. Furthermore, the measured advance of periastron of the pulsar suggests a more compact companion, for example, a main-sequence star with radius only a few times that of the sun. Such a companion is also more consistent with the small dispersion measure variations seen near periastron. Although we cannot conclusively rule out a black-hole companion, we believe the companion is probably an early B star, making the system similar to the binary PSR J0045-7319.

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I. H. Stairs, R. N. Manchester, A. G. Lyne, V. M. Kaspi, F. Camilo, J. F. Bell, N. D'Amico, M. Kramer, F. Crawford, D. J. Morris, A. Possenti, N. P. F. McKay, S. L. Lumsden, L. E. Tacconi-Garman, R. D. Cannon, N. C. Hambly, P. R. Wood. 2001-02-26. PSR J1740-3052 - a pulsar with a massive companion. https://doi.org/10.1046/j.1365-8711.2001.04447.x

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