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arXiv · 2507.18669

Search for binary companions around millisecond pulsars

Arpita Choudhary
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Abstract

It is believed that the radio pulsars rotating at spin periods of about 30 millisecond or even lower got such high spins through the transfer of angular momentum by accreting matter from their binary companions (or past companions) in the past. Around 35% of MSPs are known to be isolated, some of the which might actually be in binaries - either not timed very well to obtain the signature of the orbit or in extremely wide binaries that can be revealed only through very accurate timing, as in the case of PSR J1024-0719. This has motivated an exercise to identify probable candidates of companions of MSPs in the Galactic field. This exercise has even the potential of discovering optical emission from MSPs themselves. Discovery of any possible binary companion will be followed by motivated pulsar timing campaigns to confirm the binary nature and to constrain orbital parameters.

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Arpita Choudhary. 2025-07-24. Search for binary companions around millisecond pulsars. https://arxiv.org/abs/2507.18669

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