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A new bursting X-ray transient: SAX J1750.8-2900

L. Natalucci·R. Cornelisse·A. Bazzano·M. Cocchi·P. Ubertini·J. Heise·J. J. M. in 't Zand·E. Kuulkers
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Abstract

We have analysed in detail the discovery measurements of the X-ray burster SAX J1750.8-2900 by the Wide Field Cameras on board BeppoSAX in spring 1997, at a position ~1.2 degrees off the Galactic Centre. The source was in outburst on March 13th when the first observation started and showed X-ray emission for ~ 2 weeks. A total of 9 bursts were detected, with peak intensities varying from ~ 0.4 to 1.0 Crab in the 2-10 keV range. Most bursts showed a fast rise time (~ 1s), an exponential decay profile with e-folding time of ~ 5s, spectral softening during decay, and a spectrum which is consistent with few keV blackbody radiation. These features identify them as type-I X-ray bursts of thermonuclear origin. The presence of type-I bursts and the source position close to the Galactic Centre favours the classification of this object as a neutron star low mass X-ray binary. X-ray emission from SAX J1750.8-2900 was not detected in the previous and subsequent Galactic bulge monitoring, and the source was never seen bursting again.

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L. Natalucci, R. Cornelisse, A. Bazzano, M. Cocchi, P. Ubertini, J. Heise, J. J. M. in 't Zand, E. Kuulkers. 1999-07-21. A new bursting X-ray transient: SAX J1750.8-2900. https://doi.org/10.1086/312263

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