[vsnet-grb-info 5194] GRB 071011: XRT afterglow detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6891
SUBJECT: GRB 071011: XRT afterglow detection
DATE:    07/10/11 18:24:21 GMT
FROM:    Boris Sbarufatti at INAF-IASF-Pa  <sbarufatti at ifc.inaf.it>

B. Sbarufatti, V. La Parola, E. Troja, V. Mangano (INAF-IASFPA),
J. Kennea (PSU), F.E. Marshall (GSFC) report on behalf of the
Swift-XRT team.

We have analyzed the first orbit of XRT data of the Swift
observation of GRB 071011 (Marshall et al., GCN 6882), started
at 13:28:40 UT.
We have a 1600 sec exposure in PC mode. We detect a single
uncatalogued bright source within the XRT field of view,
across an hot column, at position
RA, Dec= 8.3887, +61.1325 deg which is

   RA(J2000)=   0h 33m 33.30s
   Dec(J2000)=  +61d 07' 57.3"

with an uncertainty of 4.4 arcsec (90% containment radius). This
is 11 arcsec from the BAT refined  position (Sakamoto et al,
GCN 6889). We remark that the new BAT error circle excludes the
optical afterglow candidate reported by Perley et al. (GCN 6883).
A quick look to the XRT light curve gives a flat behavior at the
level of 0.3 counts/sec. We wait for more data to improve our
analysis.