PSR J1518+4904: A mildly relativistic binary pulsar system

摘要: PSR J1518+4904 is a recently discovered 40.9 ms pulsar in an 8.6 day, moderately eccentric orbit. We have measured pulse arrival times for this over 1.4 yr at several radio frequencies, from which we derived high-precision rotational, astrometric, and orbital parameters. The upper limit the period derivative of pulsar, < 4 × 10-20, gives characteristic age least 1.6 1010 yr, among highest known. find orbit to be precessing rate 00111 ± 00002 yr-1, yields total system mass (pulsar plus companion) 2.62 0.07 M☉ according general relativity. Further analysis parameters firm 1.75 on constrains companion range 0.9-2.7 M☉. These masses, together with sizable eccentricity other evidence, strongly suggest that second neutron star.