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Magnetars' Giant Flares: the case of SGR 1806-20

Nanda Rea
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Abstract

We first review on the peculiar characteristics of the bursting and flaring activity of the Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars. We then report on the properties of the SGR 1806-20's Giant Flare occurred on 2004 December 27th, with particular interest on the pre and post flare intensity/hardness correlated variability. We show that these findings are consistent with the picture of a twisted internal magnetic field which stresses the star solid crust that finally cracks causing the giant flare (and the observed torsional oscillations). This crustal fracturing is accompanied by a simplification of the external magnetic field with a (partial) untwisting of the magnetosphere.

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Nanda Rea. 2006-04-18. Magnetars' Giant Flares: the case of SGR 1806-20. https://doi.org/10.1088/1009-9271%2F6%2Fs1%2F19

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