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INTEGRAL observations of the peculiar BeX System SAX J2103.5+4545

P. Blay·P. Reig·S. Martinez Nunez·A. Camero·P. Connell·V. Reglero
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Abstract

We present an INTEGRAL data analysis of the X-ray transient \object{SAX J2103.5+4545} during two outbursts detected in December 2002. The INTEGRAL coordinates and error circle agree with the position of the recently proposed optical counterpart. A power-law plus cut-off model provided a good fit to the 4-150 keV spectrum yielding a photon index of 1.0+-0.1, a cut-off energy E_cut=7.6+-2.0 keV and a folding energy E_fold=30.9+-2.5 keV. The X-ray luminosity in the 4-150 keV energy range was found to be 6.0x10^36 erg/s, assuming a distance of 6.5 kpc. This luminosity, together with the derived photon index, indicate that the source is in a bright state. A 354.9$+-0.5 second pulse period is measured. This value is significantly smaller than previous measurements, indicating a long-term spin-up episode.

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P. Blay, P. Reig, S. Martinez Nunez, A. Camero, P. Connell, V. Reglero. 2004-07-28. INTEGRAL observations of the peculiar BeX System SAX J2103.5+4545. https://doi.org/10.1051/0004-6361%3A20041214

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