The PSR J0514-4002A Binary System in NGC 1851

摘要

Using the Giant Metrewave Riulio Telescope (GMRT), we have discovered PSR J0514-4002A, a binary millisecond pulsar in the globular' cluster NGC 1851. This pulsar has a rotational period of 4.99 ms and the most eccentric pulsar orbit yet found, with e = 0.89. The orbital period is 18.8 days, and the companion has a minimum mass of 0.9 M?; its nature is presently unclear. After accreting matter from a low-mass stellar companion, this pulsar exchanged it for its more massive present companion. This system presents the strongest evidence to date of such a process.