PSR J1753-2240: A mildly recycled pulsar in an eccentric binary system

TL;DR

This paper reports the discovery of PSR J1753-2240, a mildly recycled pulsar in an eccentric binary system, likely involving a neutron star companion, with implications for understanding binary evolution.

Contribution

The paper presents the discovery and initial characterization of a new eccentric binary pulsar system, providing insights into its nature and potential implications for neutron star binary evolution.

Findings

Pulsar has a 95-ms period and 13.6-day orbit.

Characteristic age exceeds 1 billion years.

Companion mass constrained to be above 0.48 solar masses.

Abstract

We report the discovery of PSR J1753-2240 in the Parkes Multibeam Pulsar Survey database. This 95-ms pulsar is in an eccentric binary system with a 13.6-day orbital period. Period derivative measurements imply a characteristic age in excess of 1 Gyr, suggesting that the pulsar has undergone an episode of accretion-induced spin-up. The eccentricity and spin period are indicative of the companion being a second neutron star, so that the system is similar to that of PSR J1811-1736, although other companion types cannot be ruled out at this time. The companion mass is constrained by geometry to lie above 0.48 solar masses, although long-term timing observations will give additional constraints. If the companion is a white dwarf or main sequence star, optical observations may yield a direct detection of the companion. If the system is indeed one of the few known double neutron star systems, it would lie significantly far from the recently proposed spin-period/eccentricity relationship.