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INTEGRAL observations of the X-ray burster 4U1850-087: first detection of hard X-ray emission extending above 50keV

Lara Sidoli·Ada Paizis·Angela Bazzano·Sandro Mereghetti
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Abstract

The X-ray burster 4U1850-087, located in the globular cluster NGC6712, is an ultracompact binary likely harbouring a degenerate companion.The source has been observed with INTEGRAL several times, during the monitoring of the Galactic plane, with an unprecedented exposure time. The broad-band spectrum (2-100 keV; INTEGRAL together with a quasi-simultaneous XMM-Newton observation) is well described with a disk-blackbody emission (kTin=0.8keV) together with a power-law (photon index of 2). We report here the first detection of hard X-ray emission from this source above 50 keV. A lower limit on the presence of a high energy cut-off can be placed at Ec>100keV.

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Lara Sidoli, Ada Paizis, Angela Bazzano, Sandro Mereghetti. 2006-10-30. INTEGRAL observations of the X-ray burster 4U1850-087: first detection of hard X-ray emission extending above 50keV. https://arxiv.org/abs/astro-ph/0610892

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