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Two long-period X-ray pulsars detected in the SMC field around XTE J0055-727

F. Haberl·W. Pietsch·N. Schartel·P. Rodriguez·R. H. D. Corbet
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Abstract

An XMM-Newton target of opportunity observation of the field around the transient 18.37 s pulsar XTE J0055-727 in the Small Magellanic Cloud (SMC) revealed two bright, long-period X-ray pulsars in the EPIC data. A new pulsar, XMMU J005517.9-723853, with a pulse period of 701.7 +/- 0.8 s was discovered and 500.0 +/- 0.2 s pulsations were detected from XMMU J005455.4-724512 (= CXOU J005455.6-724510), confirming the period found in Chandra data. We derive X-ray positions of RA = 00h5455.88s, Dec = -72d45m10.5s and RA = 00h55m18.44s, Dec = -72d38m51.8s (J2000.0) with an uncertainty of 0.2'' utilizing optical identification with OGLE stars. For both objects, the optical brightness and colours and the X-ray spectra are consistent with Be/X-ray binary systems in the SMC.

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F. Haberl, W. Pietsch, N. Schartel, P. Rodriguez, R. H. D. Corbet. 2004-05-03. Two long-period X-ray pulsars detected in the SMC field around XTE J0055-727. https://doi.org/10.1051/0004-6361%3A20040156

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