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Discovery of a 1247 s pulsar in the Be X-ray binary SAX J2239.3+6116

J. J. M. in 't Zand·J. Swank·R. H. D. Corbet·C. B. Markwardt
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Abstract

A search for pulsations from the Be X-ray binary SAX J2239.3+6116, through observations with the Narrow Field Instruments on BeppoSAX and the Proportional Counter Array on RXTE, yielded the clear presence of a 1247 s coherent oscillation. Given the fairly high X-ray luminosity on previous occasions (up to a few times 10^36 erg/s in 2 to 28 keV), the oscillation must be due to the spin of a neutron star. Assuming that the 262 day recurrence time is the orbital period, SAX J2239.3+6116 has both the longest orbital period and the longest pulse period of 24 Be X-ray binaries with measured orbital periods.

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J. J. M. in 't Zand, J. Swank, R. H. D. Corbet, C. B. Markwardt. 2001-10-31. Discovery of a 1247 s pulsar in the Be X-ray binary SAX J2239.3+6116. https://doi.org/10.1051/0004-6361%3A20011512

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