TITLE:   GCN CIRCULAR
NUMBER:  19883
SUBJECT: GRB 160829A: Swift-XRT observations
DATE:    16/08/30 09:16:42 GMT
FROM:    Andy Beardmore at U Leicester  <ab271@leicester.ac.uk>

A. Maselli  (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo
(INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), T.G.R.
Roegiers (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester) and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 160829A (Racusin et al. GCN Circ. 19879),
collecting 4.8 ks of Photon Counting (PC) mode data between T0+37.4 ks
and T0+61.4 ks. 

No X-ray source has been detected within the LAT error region (Racusin
et al. GCN Circ. 19879), with a 3 sigma upper limit count rate of
2.6e-3 ct/s (0.3-10keV). 

An uncatalogued X-ray source was detected 13.3 arcmin from the LAT
position at a count rate of (4.9 +/- 1.9)e-3 ct/s. This source is
identified by SIMBAD as CD-56 4975 at RA, Dec (J2000) = 13h 28m 03.68s,
-56d 54m 30.38s, whose colours are suggestive of a late-type star,
which is, therefore, unlikely to be related to the LAT burst.

The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
http://www.swift.ac.uk/ToO_GRBs/00020687.

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