PSR J1756-2251: a new relativistic double neutron star system
Abstract
We report the discovery during the Parkes Multibeam Pulsar Survey of PSR J1756-2251, a 28.5 ms pulsar in a relativistic binary system. Subsequent timing observations showed the pulsar to have an orbital period of 7.67 hrs and an eccentricity of 0.18. They also revealed a significant advance of periastron, 2.585+/-0.002 deg./yr. Assuming this is entirely due to general relativity implies a total system mass (pulsar plus companion) of 2.574+/-0.003 solar mass. This mass and the significant orbital eccentricity suggest that this is a double neutron star system. Measurement of the gravitational redshift, gamma, and an evaluation of the Shapiro delay shape, s, indicate a low companion mass of <1.25 solar mass. The expected coalescence time due to emission of gravitational waves is only ~1.7 Gyr substantially less than a Hubble time. We note an apparent correlation between spin period and eccentricity for normally evolving double neutron star systems.
Cite
@article{arxiv.astro-ph/0411796,
title = {PSR J1756-2251: a new relativistic double neutron star system},
author = {A. J. Faulkner and M. Kramer and A. G. Lyne and R. N. Manchester and M. A. McLaughlin and I. H. Stairs and G. Hobbs and A. Possenti and D. R. Lorimer and N. D'Amico and F. Camilo and M. Burgay},
journal= {arXiv preprint arXiv:astro-ph/0411796},
year = {2009}
}
Comments
Accepted by ApJ Letters. 4 published pages, 3 figures and 2 tables