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Register a new userOn the Fast Spectral Variability of GRBs
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E.P. Mazets
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Fast spectral variability of gamma-ray burst emission is considered for a number of events seen by the Konus-Wind experiment. The variability manifests itself as a strong correlation between instantaneous energy flux $F$ and peak energy $E_p$. In the ($F,E_p$) plane, the correlation produces distinct tracks in the form of branches and loops representing the different parts of a burst time history. Despite the variety of features seen in different events, the main characteristics of the spectral evolution produce a quite consistent pattern.
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The Swift satellite has observed more than a thousand GRBs with X-ray data. Almost a third of them have redshift measurement, too. Here we start to investigate the X-ray spectral fitting of the data considering the low energy part where the N(H) absorption happens. Based on the available more accurate input data we examined the robustness of previous fittings and tested how sensitive the changes of the starting parameters are. We studied the change of the intrinsic hydrogen column density during the outburst for a few events. No significant variability of N(H) column density was identified.
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