TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  5463
SUBJECT: GRB060813: Break in the XRT light curve 
DATE:    06/08/17 17:09:15 GMT
FROM:    Alberto Moretti at Obs Brera Merate  <alberto.moretti@brera.inaf.it>

A. Moretti (INAF-OAB), P. Romano (INAF-OAB), C. Guidorzi
(Univ. Bicocca & INAF-OAB), D.N. Burrows (PSU), N. Gehrels (GSFC)
report on behalf of the Swift-XRT team:

Based on the most recent downlinked data on GRB060813 (trigger number
224364) we find clear evidence of a break in the light curve at
48(+/-10) ks from the burst trigger (see the light curve at
http://www.brera.inaf.it/~moretti/grbplot/xrt060813.gif )
which could be a jet break.
The light curve slope steepens from 1.20+/-0.10 to 2.50+/-0.30 .
(errors are quoted at 90% confidence level).
In order to convert the XRT count rate to absorbed (unabsorbed)
flux the conversion factor is 6.1E-11 (8.1E-11).

Therefore we encourage optical data collection on this GRB, when
possible.

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