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arXiv · astro-ph/0203080

FREGATE observation of a strong burst from SGR1900+14

J-F. Olive·K. Hurley·J-P. Dezalay·J-L. Atteia·C. Barraud·N. Butler·G. B. Crew·J. Doty·G. Ricker·R. Vanderspek
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Abstract

After a long period of quiescence, the soft gamma repeater SGR1900+14 was suddenly reactivated on April 2001. On July 2, 2001, a bright flare emitted by this source triggerred the WXM and FREGATE instruments onboard the HETE-2 satellite. Unlike typical short (0.1 s) and spiky SGRs recurrent bursts, this event features a 4.1 s long main peak, with a sharp rise (50 ms) and a slower cutoff (250 ms). This main peak is followed by a 2 sec decreasing tail. We found no evidence of any precursor or any extended `afterglow' tail to this burst. We present the preliminary spectral fits of the total emission of this flare as observed by the FREGATE instrument between 7 and 150 keV. The best fit is obtained with a model consisting of two blackbody components of temperatures 4.15 keV and 10.4 keV. A thermal bremsstrahlung can not be fitted to this spectrum. We compare these features and the burst energetics with the other strong or giant flares from SGR1900+14.

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J-F. Olive, K. Hurley, J-P. Dezalay, J-L. Atteia, C. Barraud, N. Butler, G. B. Crew, J. Doty, G. Ricker, R. Vanderspek. 2002-03-06. FREGATE observation of a strong burst from SGR1900+14. https://doi.org/10.1063/1.1579307

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