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A Binary Millisecond Pulsar in Globular Cluster NGC6544

Scott M. Ransom·Lincoln J. Greenhill·James R. Herrnstein·Richard N. Manchester·Fernando Camilo·Stephen S. Eikenberry·Andrew G. Lyne
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Abstract

We report the detection of a new 3.06 ms binary pulsar in the globular cluster NGC6544 using a Fourier-domain ``acceleration'' search. With an implied companion mass of ~0.01 solar masses and an orbital period of only P_b~1.7 hours, it displays very similar orbital properties to many pulsars which are eclipsed by their companion winds. The orbital period is the second shortest of known binary pulsars after 47 Tuc R. The measured flux density of 1.3 +/- 0.4 mJy at 1332 MHz indicates that the pulsar is almost certainly the known steep-spectrum point source near the core of NGC6544.

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Scott M. Ransom, Lincoln J. Greenhill, James R. Herrnstein, Richard N. Manchester, Fernando Camilo, Stephen S. Eikenberry, Andrew G. Lyne. 2000-10-12. A Binary Millisecond Pulsar in Globular Cluster NGC6544. https://doi.org/10.1086/318062

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