Discovery of Three Binary Millisecond Pulsars
M. Bailes (NRAL, Jodrell Bank, University of Manchester, UK),
P. A. Harrison (NRAL, Jodrell Bank, University of Manchester, UK),
D. R. Lorimer (NRAL, Jodrell Bank, University of Manchester, UK),
S. Johnston (RCfTA, University of Sydney, Australia),
A. G. Lyne (NRAL, Jodrell Bank, University of Manchester, UK),
R. N. Manchester (ATNF, CSIRO, Australia),
N. D'Amico (University of Palermo and IRA - CNR, Bologna, Italy),
L. Nicastro (IRA - CNR, Bologna, Italy),
T. M. Tauris (Institute of Physics and Astronomy, Aarhus University, Denmark),
C. Robinson (NRAL, Jodrell Bank, University of Manchester, UK)
Abstract We report the discovery of three binary millisecond pulsars in circular orbits with low-mass companions from a continuing survey of the southern sky with the Parkes radio telescope. The three pulsars, PSRs J0034-0534, J1045-4509 and J2145-0750 have pulse periods of 1.87, 7.47, and 16.05 ms, and orbital periods of 1.6, 4.1 and 6.8 days respectively. PSR J2145-0750 has a spin-down age of approx 12 Gyr, which raises interesting questions about its progenitor and initial pulse period. The properties of the growing class of radio pulsars with low-mass companions are discussed, and we suggest that their velocities, and a tendency for the short-period pulsars to have small orbital periods, are consistent with their formation from type II supernova explosions.
Key Words:pulsars: individual: PSR J0034-0534, PSR J1045-4509, PSR J2145-0750 --- pulsars: formation