Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 31910

GRB 220412B: Swift-BAT refined analysis
2022-04-16T12:16:02Z (2 years ago)
Tyler Parsotan at UMBC/GSFC/CRESST II <>
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), 

H. A. Krimm (NSF), S. Laha (GSFC/UMBC),

A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),

D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),

M. Stamatikos (OSU) (i.e. the Swift-BAT team):


Using the data set from T-240 to T+40 sec sec from the recent telemetry downlink,

we report further analysis of BAT GRB 220412B (trigger #1102329)

(Gropp et al. GCN Circ. 31886).  The BAT ground-calculated position is

RA, Dec = 320.758, -0.261 deg which is 

   RA(J2000)  =  21h 23m 01.9s 

   Dec(J2000) = -00d 15' 38.5" 

with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).

The partial coding was 75%.


The BAT light curve showed a single-peaked

structure. T90 (15-350 keV) is 0.14 +- 0.04 sec 

(estimated error including systematics).


The time-averaged spectrum from T-0.03 to T+0.16 sec is best fit by a simple

power-law model.  The power law index of the time-averaged spectrum is

1.17 +- 0.20.  The fluence in the 15-150 keV band is 8.9 +- 1.2 x 10^-08 erg/cm2.

The 1-sec peak photon flux measured from T-0.44 sec in the 15-150 keV band

is 1.0 +- 0.2 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