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arXiv · astro-ph/0612437

IGR J08408--4503: a new recurrent Supergiant Fast X-ray Transient

D. Gotz·M. Falanga·F. Senziani·A. De Luca·S. Schanne·A. von Kienlin
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Abstract

The supergiant fast X-ray transient IGR J08408-4503 was discovered by INTEGRAL on May 15, 2006, during a bright flare. The source shows sporadic recurrent short bright flares, reaching a peak luminosity of 10^36 erg s^-1 within less than one hour. The companion star is HD 74194, an Ob5Ib(f) supergiant star located at 3 kpc in the Vela region. We report the light curves and broad-band spectra (0.1-200 keV) of all the three flares of IGR J08408-4503 detected up to now based on INTEGRAL and Swift data. The flare spectra are well described by a power-law model with a high energy cut-off at ~15 keV. The absorption column density during the flares was found to be ~10^21 cm^-2, indicating a very low matter density around the compact object. Using the supergiant donor star parameters, the wind accretion conditions imply an orbital period of the order of one year, a spin period of the order of hours and a magnetic field of the order of 10^13 G.

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D. Gotz, M. Falanga, F. Senziani, A. De Luca, S. Schanne, A. von Kienlin. 2006-12-15. IGR J08408--4503: a new recurrent Supergiant Fast X-ray Transient. https://doi.org/10.1086/511818

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