Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 23377

GRB 181023A: Swift-BAT refined analysis
2018-10-24T01:39:15Z (6 years ago)
Amy Lien at GSFC <>
T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), M. Stamatikos (OSU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 181023A (trigger #868427)
(Marshall et al., GCN Circ. 23366).  The BAT ground-calculated position is
RA, Dec = 248.322, 19.581 deg which is
  RA(J2000)  =  16h 33m 17.4s
  Dec(J2000) = +19d 34' 51.2"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 53%.

The mask-weighted light curve shows a complex structure with some
weak overlapping pulses that starts at ~T-30 s and ends at ~T+40 s.
Note that the burst entered the BAT FOV at T-48 s, and hence there might
be additional emission beforehand. T90 (15-350 keV) is 58.0 +- 8.8 sec (estimated
error including systematics).

The time-averaged spectrum from T-27.62 to T+36.68 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.74 +- 0.24.  The fluence in the 15-150 keV band is 1.3 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+32.18 sec in the 15-150 keV band
is 1.0 +- 0.3 ph/cm2/sec.  All the quoted errors are at the 90% confidence

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