TITLE: GCN CIRCULAR NUMBER: 19207 SUBJECT: SGR 0755-2933, Swift-BAT refined analysis DATE: 16/03/17 22:10:48 GMT FROM: Amy Lien at GSFC S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-60 to T+303 sec from the recent telemetry downlink, we report further analysis of SGR 0755-2933 (trigger #679432) (Barthelmy, et al., GCN Circ. 19204). The BAT ground-calculated position is RA, Dec = 118.863, -29.572 deg which is RA(J2000) = 07h 55m 27.0s Dec(J2000) = -29d 34' 20.3" with an uncertainty of 3.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 64%. The mask-weighted light curve shows a single short spike of duration ~ 30 ms. There is significant emission only below 50 keV. T90 (15-25 keV) is 0.024 +- 0.009 sec (estimated error including systematics). The time-averaged spectrum from T-0.004 to T+0.024 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 3.81 +- 0.74. The fluence in the 15-150 keV band is 5.9 +- 1.8 x 10^-9 erg/cm2. The 1-sec peak photon flux measured from T-0.49 sec in the 15-150 keV band is 0.3 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence level. As of T+19 hours, BAT has detected no further bursts from this source, and the BAT on-board detection history shows no previous signs of activity over the life of the mission since 2005. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/679432/BA/