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GCN Circular 32671

GRB 221009A: Continued Swift/XRT observations
2022-10-10T22:17:35Z (2 years ago)
Aaron Tohuvavohu at U Toronto <>
A. Tohuvavohu (U. Toronto), A.P. Beardmore (U. Leicester), J.P. Osborne
(U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E.
Ambrosi  (INAF-IASFPA) , B. Sbarufatti (PSU), D.N. Burrows (PSU) and
M. Williams (PSU), report on behalf of the Swift-XRT team:

Swift XRT has continued to observe GRB 221009A  from 159s to 100 ks
after the BAT trigger. The WT-mode spectrum for the afterglow was
given in GCN 32651.

The lightcurve can be best modelled as a four-component power law decay with:
Alpha_1 : 2.6 (+0.4, -0.7)
Tbreak_1: 177.4 (+2.0, -9.6)
Alpha_2 : 0.144 (+0.022, -0.026)
Tbreak_2: 610 (+84, -78)
Alpha_3 : 0.31 (+0.04, -0.03)
Tbreak_3: (4.06 [+0.23, -0.19]) �� 10^3
Alpha_4 : 1.357 (+/-0.010)

With T0 the BAT trigger time.

The results of the XRT-team automatic analysis are available at

This circular is an official product of the Swift-XRT team.
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