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GCN Circular 6327

Subject

GRB 070419B, Swift-BAT refined analysis

Date

2007-04-20T02:39:09Z (18 years ago)

From

Ann M. Parsons at NASA/GSFC/Swift <parsons@milkyway.gsfc.nasa.gov>

D. Palmer (LANL), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), A. Parsons (GSFC),
T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), and J. Tueller (GSFC)
on behalf of the Swift-BAT team:

Using the data set from T-239.9 to T+602.1 sec from the recent
telemetry downlink, we report further analysis of BAT GRB 070419
(trigger #276212)   (Parsons, et al., GCN Circ. 6305Not found
 
 
).  The BAT
ground-calculated position is RA, Dec = 315.709, -31.266 deg which is
     RA(J2000) = 21h 2m 50.2s
     Dec(J2000) = -31d 15' 58.3"
with an uncertainty of 1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 66%.

The mask-weighted light curve exhibits 4 main peaks at ~T+0 s,T+25s,
T+35s, and T+60s and its duration T90 (15-350 keV) is 236.5 +-12 sec
(estimated error including systematics).

The time-averaged spectrum from -11.7 to 314.8 s is best fit by
a simple power-law model.  The power law index of the time-averaged
spectrum is 1.70 +- 0.05. The fluence in the 15-150 keV band is
7.5 +- 0.2 x 10^-6 erg/cm2.The 1-sec peak photon flux measured from
T-0.28 sec in the 15-150 keV band is 1.4 +- 0.2 ph/cm2/sec.  All the
quoted errors are at the 90% confidence level.