GCN Circular 2917
Subject
GRB041219; RXTE ASM Observations
Date
2004-12-28T16:42:09Z (20 years ago)
From
Al Levine at MIT <aml@space.mit.edu>
Alan Levine and Ron Remillard (MIT) on behalf of the RXTE ASM Team
at MIT and GSFC:
GRB041219 (Mereghetti et al., GCN Circular 2866; and Barthelmy et al.,
GCN Circular 2874) was observed during two dwells, each of duration 90
s, with Scanning Shadow Camera 3 of the RXTE ASM. The observations
cover the interval 2004 December 19 1:42:24 to 1:45:30 UTC except for
a single 6 s gap in the middle of the interval. Automated real-time
analysis of RXTE ASM data yielded a detection of GRB041219 and an
error box:
RA, Dec (error box center; J2000): 7.085 62.727 degrees
Position angle of the error box long direction): 105.72 degrees
Error box half width: 0.037 degrees
Error box half length: 0.7 degrees
in which is found the position derived by Bloom et al. (GCN Circular
2893).
In count rate data, the event appears as a single peak with possible
substructure lasting about 50 s in the 1.5-3 keV and 3-5 keV bands and
about 25 s in the 5-12 keV band. The peak fluxes were approximately
3, 4 and 6 Crab in the 1.5-3, 3-5, and 5-12 keV bands, respectively.
The initial sharp rise of this peak (best defined in the 5-12 keV
band) occurs at UTC 2004:354:01:43:30 with an uncertainty of about 2
seconds. The background before this time appears to vary; this could
be the tail of an earlier GRB-related peak or it could be variation of
an unrelated source. The times quoted herein are times at the
position of the spacecraft; they have not been corrected to the
barycenter of the solar system.
In the time interval covered by the ASM, the Swift BAT light curves
(Fenimore et al., GCN Circular 2906) show a single relatively
inconspicuous small enhancement that appears to start at about the
same time as the peak seen in the ASM data. The ASM coverage does not
cover the first peak seen by BAT or the later strong peaks.
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