TITLE: GCN CIRCULAR NUMBER: 12983 SUBJECT: GRB 120224A: Swift-BAT refined analysis DATE: 12/02/24 13:26:41 GMT FROM: Scott Barthelmy at NASA/GSFC S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), C. J. Saxton (UCL-MSSL), 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+326 sec from the recent telemetry downlink, we report further analysis of BAT GRB 120224A (trigger #515976) (Saxton, et al., GCN Circ. 12980). The BAT ground-calculated position is RA, Dec = 40.937, -17.779 deg, which is RA(J2000) = 02h 43m 44.8s Dec(J2000) = -17d 46' 42.6" with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 29%. The mask-weighted light curve shows two peaks, the first starting at ~T-20 sec, peaking at ~T-6 sec. The second (and stronger peak) starts at ~T-3 sec, peaks at ~T+1 sec, and ends at ~T+13 sec. T90 (15-350 keV) is 8.13 +- 1.99 sec (estimated error including systematics). The time-averaged spectrum from T-1.08 to T+8.26 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.25 +- 0.36. The fluence in the 15-150 keV band is 2.4 +- 0.5 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.24 sec in the 15-150 keV band is 0.9 +- 0.2 ph/cm2/sec. 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/515976/BA/