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

GCN Circular 16423

Subject
GRB 140619A: Swift-BAT refined analysis
Date
2014-06-20T12:24:35Z (10 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC), M. De Pasquale (INAF-IASFPA)
T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):

Using the data set from T-239 to T+421 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 140619A (trigger #602080)
(De Pasquale, et al., GCN Circ. 16415).  The BAT ground-calculated position is
RA, Dec = 27.096, -39.249 deg which is
   RA(J2000)  =  01h 48m 23.2s
   Dec(J2000) = -39d 14' 57.1"
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 41%.

The mask-weighted light curve shows a complex structure with multiple peaks.
The main visible structure starts with roughly two long weaker pulses from
~T+20 s to T+150 s. The two weak pulses were followed by the major bright
structure lasting until ~T+260 s, and it consists of many sub-pulses. Afterward
there is another weaker long pulse lasting until ~T+350 s. T90 (15-350 keV) is
233.9 +- 13.4 sec (estimated error including systematics).

Note that the main structure of the burst happened at ~150 s after the original image trigger,
and was not described in the first circular (De Pasquale, et al., GCN Circ. 16415).

The time-averaged spectrum from T+32.3 to T+340.4 sec is best fit by a power law
with an exponential cutoff.  This fit gives a photon index 1.45 +- 0.14,
and Epeak of 117.8 +- 46.2 keV (chi squared 54.23 for 56 d.o.f.).  For this
model the total fluence in the 15-150 keV band is 2.1 +- 0.04 x 10^-5 erg/cm2
and the 1-sec peak flux measured from T+219.52 sec in the 15-150 keV band is
4.6 +- 0.2 ph/cm2/sec.  A fit to a simple power law gives a photon index
of 1.71 +- 0.03 (chi squared 64.34 for 57 d.o.f.).  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/602080/BA/
Looking for U.S. government information and services? Visit USA.gov