Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
Introducing Einstein Probe, Astro Flavored Markdown, and Notices Schema v4.0.0. See news and announcements

GCN Circular 30554

GRB 210730A: Swift-BAT refined analysis
2021-07-30T17:05:35Z (3 years ago)
Amy Lien at GSFC <>
T. Sakamoto (AGU), S. D. Barthelmy (GSFC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), E. Sonbas (Adiyaman Univ.),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):

Using the data set from T-240 to T+200 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 210730A (trigger #1062150)
(Sonbas et al., GCN Circ. 30548).  The BAT ground-calculated position is
RA, Dec = 149.570, 69.703 deg which is
   RA(J2000)  =  09h 58m 16.8s
   Dec(J2000) = +69d 42' 12.4"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 55%.

The mask-weighted light curve shows a single-peaked structure that
starts at ~T-0.5, peaks at ~T+0.5, and ends at ~T+5. T90 (15-350 keV)
is 3.86 +- 0.66 sec (estimated error including systematics).

The time-averaged spectrum from T-0.32 to T+5.01 sec is best fit by
a simple power-law model.  The power law index of the time-averaged
spectrum is 1.41 +- 0.11.  The fluence in the 15-150 keV band
is 1.3 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured
from T+0.17 sec in the 15-150 keV band is 7.1 +- 0.5 ph/cm2/sec.
All the quoted errors are at the 90% confidence level.

The results of the batgrbproduct analysis are available at
Looking for U.S. government information and services? Visit