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GCN Circular 13480

Swift-BAT refined analysis of 1E 1841-045 (Trigger=526660)
2012-07-15T13:46:50Z (12 years ago)
Scott Barthelmy at NASA/GSFC <>
S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/UMBC)
(on behalf of the Swift-BAT team):
Using the data set from T-119 to T+183 sec from recent telemetry downlinks,
we report further analysis of 1E 1841-045 (aka Kes 73) (trigger #526660)
(Barthelmy, et al., GCN Circ. 13475).  The BAT ground-calculated position is
RA, Dec = 280.374, -4.923 deg which is 
   RA(J2000)  =  18h 41m 29.8s 
   Dec(J2000) = -04d 55' 23.4" 
with an uncertainty of 2.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 44%.
The mask-weighted light curve shows a singple spike (possibly 2 overlapping spikes)
starting at ~T-0.008 and ending at ~T+0.012 sec.  T90 (15-350 keV) is 0.012 +- 0.006 sec
(estimated error including systematics).
The time-averaged spectrum from T-0.008 to T+0.012 sec fit by a simple
power-law model shows the power law index of 2.66 +- 0.40 (chi squared 50.1 for 57 d.o.f.).
The fluence in the 15-150 keV band is 1.2 +- 0.3 x 10^-8 erg/cm2.
A single blackbody fit to the time-averaged spectrum shows the blackbody
temperature of 8.77 +- 1.67 keV (chi squared 40.8 for 59 d.o.f.).
All the quoted errors are at the 90% confidence level. 
The results of the batgrbproduct analysis are available at

We note the previous activity of this source: Swift BAT triggers 456505
on 02 Jul 2011 (GCN 12103 & 12104), 455904 on 23 Jun 2011 (GCN 12079 & 12082), and
445776 on 11 Feb 2011 (GCN 11673).
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