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GCN Circular 26327

Subject

GRB 191130A, a long burst detected in Swift-BAT ground analysis

Date

2019-12-03T15:22:09Z (4 years ago)

From

Amy Lien at GSFC <amy.y.lien@nasa.gov>

D. M. Palmer (LANL), A. Y. Lien (GSFC/UMBC), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

At 13:05:02 UT on 2019-11-30, GRB 191130A occurred during a
preplanned slew of the Neil Gehrels Swift Observatory and was
later found in the Swift/BAT ground analysis.

Using the data set from T-139 to T+106 sec from the recent telemetry
downlink (observation ID: 03110538005),
the BAT ground-calculated position is
RA, Dec = 133.137, 5.017 deg which is
   RA(J2000)  =  08h 52m 32.9s
   Dec(J2000) = +05d 01' 02.1"
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).

The mask-weighted light curve shows a single-pulse structure that starts
at ~T0, peaks at ~T+7 s, and ends at ~T+22 s. T90 (15-350 keV)
is 17.6 +- 2.9 sec (estimated error including systematics).

The time-averaged spectrum from T-0.0 to T+22.1 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.95 +- 0.13.  The fluence in the 15-150 keV band is 6.86 +- 0.6 x 10^-7
erg/cm2.
The 1-sec peak photon flux measured from T+6.18 sec in the 15-150 keV band
is 1.1 +- 0.2 ph/cm2/sec.  All the quoted errors are at the 90% confidence
level.

The results of the batgrbproduct analysis are available at
https://swift.gsfc.nasa.gov/results/BATbursts/GRB191130A/03110538005/bascript/top.html