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arXiv · astro-ph/0511587

Transient radio bursts from rotating neutron stars

M. A. McLaughlin·A. G. Lyne·D. R. Lorimer·M. Kramer·A. J. Faulkner·R. N. Manchester·J. M. Cordes·F. Camilo·A. Possenti·I. H. Stairs·G. Hobbs·N. D'Amico·M. Burgay·J. T. O'Brien
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Abstract

The `radio sky' is relatively unexplored for transient signals, although the potential of radio-transient searches is high, as demonstrated recently by the discovery of a previously unknown type of source which varies on timescales of minutes to hours. Here we report a new large-scale search for radio sources varying on much shorter timescales. This has revealed 11 objects characterized by single, dispersed bursts having durations between 2 and 30 ms. The average time intervals between bursts range from 4 minutes to 3 hours, with radio emission typically detectable for < 1 s per day. From an analysis of the burst arrival times, we have identified periodicities in the range 0.4 - 7 s for ten of the 11 sources, suggesting a rotating neutron star origin. Despite the small number of sources presently detected, their ephemeral nature implies a total Galactic population which significantly exceeds that of the regularly pulsing radio pulsars. Five of the ten sources have periods greater than 4 s, and period derivatives have been measured for three of the sources, with one having a very high inferred magnetic field of 5e13 G, suggesting that this new population is related to other classes of isolated neutron stars observed at X-ray and gamma-ray wavelengths.

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M. A. McLaughlin, A. G. Lyne, D. R. Lorimer, M. Kramer, A. J. Faulkner, R. N. Manchester, J. M. Cordes, F. Camilo, A. Possenti, I. H. Stairs, G. Hobbs, N. D'Amico, M. Burgay, J. T. O'Brien. 2005-11-22. Transient radio bursts from rotating neutron stars. https://doi.org/10.1038/nature04440

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