TITLE:   GCN CIRCULAR
NUMBER:  37772
SUBJECT: GRB 241009A: Swift-XRT afterglow detection
DATE:    24/10/11 15:47:40 GMT
FROM:    Phil Evans at U of Leicester <pae9@star.le.ac.uk>

M. A. Williams (PSU), S. Dichiara (PSU), J.A. Kennea (PSU), J.P.
Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester), C. Salvaggio (INAF-OAB), M. Ferro (INAF-OAB), R. Brivio
(INAF-OAB) and P.A. Evans (U. Leicester) reports on behalf of the
Swift-XRT team:

Swift-XRT has performed follow-up observations of the
SVOM/ECLAIRs-detected burst GRB 241009A, collecting 2.1 ks of Photon
Counting (PC) mode data between T0+14.7 ks and T0+106.0 ks. 

Seven uncatalogued X-ray sources are detected, of which one ("Source
1") is believed to be the afterglow. Using 433 s of PC mode data and 1
UVOT image, we find an enhanced XRT position (using the XRT-UVOT
alignment and matching UVOT field sources to the USNO-B1 catalogue):
RA, Dec = 325.00866, -35.65944 which is equivalent to:

RA (J2000): 21h 40m 02.08s
Dec(J2000): -35d 39' 34.0"

with an uncertainty of 4.2 arcsec (radius, 90% confidence). This
position is 6.3 arcmin from the SVOM/ECLAIRs position. The source has
faded from a count rate of 0.0441 [+0.013, -0.011] ct s^-1 at T0+14.9
ks to an upper limit of 0.0132 ct s^-1 at T0+100.9 ks.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00021722.
The results of the full analysis of the XRT observations are available
at https://www.swift.ac.uk/ToO_GRBs/00021722.

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