Discovery of a 1247 s pulsar in the Be X - ray binary SAX J 2239 . 3 + 6116
نویسنده
چکیده
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 erg s−1 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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The transient X - ray source SAX J 2239 . 3 + 6116 and its optical counterpart
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