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Discovery of Five Binary Radio Pulsars

F. Camilo·A. G. Lyne·R. N. Manchester·J. F. Bell·I. H. Stairs·N. D'Amico·V. M. Kaspi·A. Possenti·F. Crawford·N. P. F. McKay·.
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Abstract

We report on five binary pulsars discovered in the Parkes multibeam Galactic plane survey. All of the pulsars are old, with characteristic ages 1-11 Gyr, and have relatively small inferred magnetic fields, 5-90e8 G. The orbital periods range from 1.3 to 15 days. As a group these objects differ from the usual low-mass binary pulsars (LMBPs): their spin periods of 9-88 ms are relatively long; their companion masses, 0.2-1.1 Msun, are, in at least some cases, suggestive of CO or more massive white dwarfs; and some of the orbital eccentricities, 1e-5 < e < 0.002, are unexpectedly large. We argue that these observed characteristics reflect binary evolution that is significantly different from that of LMBPs. We also note that intermediate-mass binary pulsars apparently have a smaller scale-height than LMBPs.

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F. Camilo, A. G. Lyne, R. N. Manchester, J. F. Bell, I. H. Stairs, N. D'Amico, V. M. Kaspi, A. Possenti, F. Crawford, N. P. F. McKay, .. 2000-12-07. Discovery of Five Binary Radio Pulsars. https://doi.org/10.1086/319120

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