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GCN Circular 12317

Subject

SGR Swift J1834.9-0846: Swift-BAT refined analysis of trigger 501752

Date

2011-08-30T13:16:15Z (13 years ago)

From

Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>

S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), E. A. Hoversten (PSU),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU),
J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-61 to T+242 sec from recent telemetry downlinks,
we report further analysis of SGR Swift J1834.9-0846 (BAT trigger #501752)
(Hoversten, et al., GCN Circ. 12316Not found
 
 
).  The BAT ground-calculated position is
RA, Dec = 278.710, -8.770 deg, which is 
   RA(J2000)  =  18h 34m 50.3s 
   Dec(J2000) = -08d 46' 11.8" 
with an uncertainty of 3.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 57%.
 
The mask-weighted light curve shows a single spike with a width of ~0.016 sec
T90 (15-350 keV) is 0.012 +- 0.001 sec (estimated error including systematics).
 
The time-averaged spectrum from T+0.000 to T+0.012 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
3.15 +- 0.63.  The fluence in the 15-150 keV band is 2.8 +- 1.2 x 10^-9 erg/cm2.
The 1-sec peak photon flux measured from T-0.49 sec in the 15-150 keV band
is 0.34 +- 0.18 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level. 
 
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/501752/BA/