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GCN Circular 24941

Subject

GRB 190630C: Swift-BAT refined analysis

Date

2019-07-01T14:58:51Z (5 years ago)

From

Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>

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

Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 190630C (trigger #912239)
(Ukwatta, et al., GCN Circ. 24927Not found
 
 
).  The BAT ground-calculated position is
RA, Dec = 293.890, -32.759 deg which is 
  RA(J2000)  =  19h 35m 33.6s 
  Dec(J2000) = -32d 45' 32.5" 
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 57%.

The mask-weighted light curve shows a single FRED-shaped burst, beginning 
at ~T-5 sec, peaking at T+0 sec, and declining to background by ~T+40 sec.
A spacecraft slew took the burst position out of the BAT field of view just before
T+500 sec. T90 (15-350 keV) is 38.4 +- 9.3 sec (estimated error including systematics).

The time-averaged spectrum from T-1.92 to T+50.23 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.96 +- 0.11.  The fluence in the 15-150 keV band is 2.3 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.12 sec in the 15-150 keV band
is 2.0 +- 0.3 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/912239/BA/