INTEGRAL observations of recurrent fast X-ray transient sources

V. Sguera; E. J. Barlow; A. J. Bird; D. J. Clark; A. J. Dean; A. B. Hill; L. Moran; S. E. Shaw; D. R. Willis; A. Bazzano; P. Ubertini; A. Malizia

doi:10.1051/0004-6361:20053103

arXiv · astro-ph/0509018

INTEGRAL observations of recurrent fast X-ray transient sources

V. Sguera·E. J. Barlow·A. J. Bird·D. J. Clark·A. J. Dean·A. B. Hill·L. Moran·S. E. Shaw·D. R. Willis·A. Bazzano·P. Ubertini·A. Malizia

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Abstract

Fast X-ray Transients (FXTs) are believed to be non-recurrent bright X-ray sources lasting less than a day and occuring at serendipitous positions, they can best detected and discovered by instruments having a sufficiently wide field of view and high sensitivity. The IBIS/ISGRI instrument onboard INTEGRAL is particularly suited to detect new or already known fast X-ray transient sources. We report on IBIS/ISGRI detection of newly discovered outbursts of three fast transient sources located at low Galactic latitude: SAX J1818.6-1703; IGR J16479-4514; IGR J17391-302/XTE J1739-302. The reported results confirm and strengthen the very fast transient nature of these sources, given that all their newly detected outbursts have a duration less than about 3 hours. Additionally, they provide the first evidence for a possible recurrent fast transient behaviour as all three sources were detected in outburst by ISGRI more than once during the last 2 years.

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V. Sguera, E. J. Barlow, A. J. Bird, D. J. Clark, A. J. Dean, A. B. Hill, L. Moran, S. E. Shaw, D. R. Willis, A. Bazzano, P. Ubertini, A. Malizia. 2005-09-01. INTEGRAL observations of recurrent fast X-ray transient sources. https://doi.org/10.1051/0004-6361%3A20053103

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