GRB 090205: Swift-BAT refined analysis
J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), M. Perri (ASDC),
T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+455 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 090205 (trigger #342121)
(Perri, et al., GCN Circ. 8884). The BAT ground-calculated position is
RA, Dec = 220.917, -27.848 deg which is
RA(J2000) = 14h 43m 40.0s
Dec(J2000) = -27d 50' 51.4"
with an uncertainty of 2.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows a single peak starting at ~T-5 sec,
peaking at ~T+3 sec, and returning to background at ~T+100 sec.
T90 (15-350 keV) is 8.8 +- 1.8 sec (estimated error including systematics).
The time-averaged spectrum from T-2.9 to T+6.6 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.15 +- 0.23. The fluence in the 15-150 keV band is 1.9 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+4.09 sec in the 15-150 keV band
is 0.5 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence
The results of the batgrbproduct analysis are available at