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GCN Circular 18687

GRB 151212A: Swift-XRT afterglow detection
2015-12-12T20:48:03Z (9 years ago)
Phil Evans at U of Leicester <>
T.G.R. Roegiers (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U.
Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai
(INAF-IASFPA), L.M. McCauley (PSU), J.A. Kennea (PSU) and P.A. Evans
(U. Leicester) report on behalf of the Swift-XRT team:

Swift-XRT has performed follow-up observations of the MAXI-detected
burst GRB 151212A (Nakahira et al. GCN Circ. 18685) in a series of
observations tiled on the sky. The total exposure time is 1.3 ks,
distributed over 7 tiles; the maximum exposure at a single sky location
was 437 s. The data were collected between T0+8.4 ks and T0+8.6 ks, and
are entirely in Photon Counting (PC) mode. 

An uncatalogued X-ray source is detected and is above the RASS limit,
and is therefore likely the GRB afterglow.  The position of this source
is RA, Dec=68.1521, -3.9615 which is equivalent to:

RA (J2000): 04:32:36.50
Dec(J2000): -03:57:41.3

with an uncertainty of 5.2 arcsec (radius, 90% confidence).  This
position is 11.5 arcmin from the MAXI position.  We cannot determine at
the present time whether the source is fading.

The results of the XRT-team automatic analysis of the likely afterglow
are at
The results of the full analysis of the tiled XRT observations are
available at

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