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arXiv · 1201.2284

X-ray Pulsations from the region of the Supergiant Fast X-ray Transient IGR J17544-2619

S. P. Drave·A. J. Bird·L. J. Townsend·A. B. Hill·V. A. McBride·V. Sguera·A. Bazzano·D. J. Clark
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Abstract

Phase-targeted RXTE observations have allowed us to detect a transient 71.49 \pm 0.02 s signal that is most likely to be originating from the supergiant fast X-ray transient IGR J17544-2619. The phase-folded light curve shows a possible double-peaked structure with a pulsed flux of ~4.8*10^-12 erg cm^-2 s^-1 (3-10 keV). Assuming the signal to indicate the spin period of the neutron star in the system, the provisional location of IGR J17544-2619 on the Corbet diagram places the system within the classical wind-fed supergiant XRB region. Such a result illustrates the growing trend of supergiant fast X-ray transients to span across both of the original classes of HMXB in Porb - Pspin space.

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S. P. Drave, A. J. Bird, L. J. Townsend, A. B. Hill, V. A. McBride, V. Sguera, A. Bazzano, D. J. Clark. 2012-01-11. X-ray Pulsations from the region of the Supergiant Fast X-ray Transient IGR J17544-2619. https://doi.org/10.1051/0004-6361%2F201117947

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