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XMM-Newton observations of two transient millisecond X-ray pulsars in quiescence

S. Campana·N. Ferrari·L. Stella·G. L. Israel
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Abstract

We report on XMM-Newton observations of two X-ray transient millisecond pulsars (XRTMSPs). We detected XTE J0929-314 with an unabsorbed luminosity of \~7x10^{31} erg/s. (0.5-10 keV) at a fiducial distance of 10 kpc. The quiescent spectrum is consistent with a simple power law spectrum. The upper limit on the flux from a cooling neutron star atmosphere is about 20% of the total flux. XTE J1807-294 instead was not detected. We can put an upper limit on the source quiescent 0.5-10 keV unabsorbed luminosity <4x10^{31} erg/s at 8 kpc. These observations strenghten the idea that XRTMSPs have quiescent luminosities significantly lower than classical neutron star transients.

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S. Campana, N. Ferrari, L. Stella, G. L. Israel. 2005-03-24. XMM-Newton observations of two transient millisecond X-ray pulsars in quiescence. https://doi.org/10.1051/0004-6361%3A200500103

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