A radio pulsar/x-ray binary link.
Radio pulsars with millisecond spin periods are thought to have been spun up by the transfer of matter and angular momentum from a low-mass companion star during an x-ray-emitting phase. The spin periods of the neutron stars in several such low-mass x-ray binary (LMXB) systems have been shown to be in the millisecond regime, but no radio pulsations have been detected. Here we report on detection and follow-up observations of a nearby radio millisecond pulsar (MSP) in a circular binary orbit with an optically identified companion star. Optical observations indicate that an accretion disk was present in this system within the past decade. Our optical data show no evidence that one exists today, suggesting that the radio MSP has turned on after a recent LMXB phase.
Archibald
Anne M
AM
Department of Physics, McGill University, 3600 Rue University, Montréal, Quebec, H3A 2T8, Canada. aarchiba@physics.mcgill.ca
Stairs
Ingrid H
IH
Ransom
Scott M
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Kaspi
Victoria M
VM
Kondratiev
Vladislav I
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Lorimer
Duncan R
DR
McLaughlin
Maura A
MA
Boyles
Jason
J
Hessels
Jason W T
JW
Lynch
Ryan
R
van Leeuwen
Joeri
J
Roberts
Mallory S E
MS
Jenet
Frederick
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Champion
David J
DJ
Rosen
Rachel
R
Barlow
Brad N
BN
Dunlap
Bart H
BH
Remillard
Ronald A
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