Eight new MSPs in NGC 6440 and NGC 6441
Abstract
We report the discovery of five new millisecond pulsars in the globular cluster NGC 6440 and three new ones in NGC 6441; each cluster has one previously known pulsar. Four of the new pulsars are found in binary systems. One of the new pulsars, PSR J1748-2021B in NGC 6440, is notable for its eccentric (e = 0.57) and wide (P_b = 20.5 days) orbit. If the rate of advance of periastron is due solely to general relativity, we can estimate of the total mass of this binary system: 2.92 +/- 0.20 solar masses. This would imply an anomalously large mass for this pulsar, which could introduce important constraints in the study of the equation of state for cold neutron matter.
Keywords
Cite
@article{arxiv.0711.2028,
title = {Eight new MSPs in NGC 6440 and NGC 6441},
author = {Paulo C. C. Freire and Scott M. Ransom and Steve Begin and Ingrid H. Stairs and Jason W. T. Hessels and Lucille H. Frey and Fernando Camilo},
journal= {arXiv preprint arXiv:0711.2028},
year = {2008}
}
Comments
3 pages, 3 figures. To appear in the proceedings of "40 Years of Pulsars: Millisecond Pulsars, Magnetars, and More", August 12-17, 2007, McGill University, Montreal, Canada