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GCN Circular 2984

GRB 050126: Prompt XRT detection and localization
2005-01-26T14:16:46Z (19 years ago)
David Burrows at PSU/Swift <>
J. A. Kennea, D. N. Burrows, J. E. Hill, D. Morris, J. A. Nousek (PSU), G. 
Tagliaferri, C. Pagani, S. Campana, A. Moretti, P. Romano, G. Chincarini 
(OAB), J. Osborne, K. Page, M. Goad, A. Beardmore, A. Wells (U. Leicester), 
N. Gehrels, N. White, L. Angelini, F. Marshall (NASA/GSFC), P. Giommi 
(ASI), K. McGowan, K. Mason (MSSL) report on behalf of the Swift XRT team:

The Swift XRT instrument reports a preliminary position for GRB 
050126.  The BAT detected this burst at 12:00:53 UT on January 26, 
2005.  The S/C slewed to the burst immediately.  The XRT was in Manual 
State taking calibration observations of Mkn 876 in PC mode at the time of 
the slew.  We settled on the BAT position at 12:03:04 and immediately began 
taking data in PC mode until 12:07:42, when we entered the South Atlantic 
Anomaly.  During this four minute period the XRT detected a very bright and 
rapidly fading X-ray source.  The initial position, based on the raw image 
data with no correction for stellar aberration, is:

RA(J2000) = 18:32:25.8
Dec(J2000) = +42:22:0.4.

The estimated uncertainty in this early position is 30 arcseconds.  A more 
accurate position will be sent out when we are able to process these data 
through the pipeline software.
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