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تسجيل مستخدم جديدAn XMM-Newton observation of the neutron star X-ray transient 2S 1803-245 in quiescence
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We observed the neutron star X-ray transient 2S 1803-245 in quiescence with the X-ray satellite XMM-Newton, but did not detect it. An analysis of the X-ray bursts observed during the 1998 outburst of 2S 1803-245 gives an upper-limit to the distance of <7.3 kpc, leading to an upper-limit on the quiescent 0.5-10 keV X-ray luminosity of <2.8x10^32 erg/s (3sigma). Since the expected orbital period of 2S 1803-245 is several hrs, this limit is not much higher than those observed for the quiescent black hole transients with similar orbital periods.
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