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INTEGRAL and Magnetars

D. Gotz·S. Mereghetti·K. Hurley·I. F. Mirabel·P. Esposito·A. Tiengo·G. Weidenspointner·A. von Kienlin
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Abstract

Thanks to INTEGRAL's long exposures of the Galactic Plane, the two brightest Soft Gamma-Ray Repeaters, SGR 1806-20 and SGR 1900+14, have been monitored and studied in detail for the first time at hard-X/soft-gamma rays. SGR 1806-20, lying close to the Galactic Centre, and being very active in the past two years, has provided a wealth of new INTEGRAL results, which we will summarise here: more than 300 short bursts have been observed from this source and their characteristics have been studied with unprecedented sensitivity in the 15-200 keV range. A hardness-intensity anticorrelation within the bursts has been discovered and the overall Number-Intensity distribution of the bursts has been determined. The increase of its bursting activity eventually led to the December 2004 Giant Flare for which a possible soft gamma-ray (>80 keV) early afterglow has been detected with INTEGRAL. The deep observations allowed us to discover the persistent emission in hard X-rays (20-150 keV) from 1806-20 and 1900+14, the latter being in quiescent state, and to directly compare the spectral characteristics of all Magnetars (two SGRs and three Anomalous X-ray Pulsars) detected with INTEGRAL.

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D. Gotz, S. Mereghetti, K. Hurley, I. F. Mirabel, P. Esposito, A. Tiengo, G. Weidenspointner, A. von Kienlin. 2007-02-07. INTEGRAL and Magnetars. https://arxiv.org/abs/astro-ph/0702188

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