[vsnet-grb-info 3834] GRB 060929: Further XRT Refined Analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  5668
SUBJECT: GRB 060929: Further XRT Refined Analysis
DATE:    06/09/30 13:44:52 GMT
FROM:    Kim Page at U.of Leicester  <kpa at star.le.ac.uk>

K.L. Page, A.P. Beardmore (U. Leicester) & C.B. Markwardt (GSFC/UMD)  
report on behalf of the Swift-XRT team:

We have now analysed the first 9 orbits of XRT data obtained for GRB
060929 (GCN Circ. 5654; Markwardt et al.). Following the large flare
between T+410s and T+1180s reported in GCN Circulars 5662 and 5663 (Palmer
et al.; Beardmore et al.), the X-ray afterglow fades with a decay slope of
0.79 +/- 0.08.

Assuming this rate of decay continues, we predict a count rate of 0.0019
count s^-1 at T+24 hours. Using the spectral fit for the data after the
flare (photon index = 2.5 +/- 0.9) together with a total column density of
1.8e21 cm^-2 (see GCN Circ. 5663), this corresponds to an observed
(unabsorbed) flux of 7.49e-14 (1.41e-13) erg cm^-2 s^-1.

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