TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4289 SUBJECT: GRB 051117A: Refined analysis of the Swift-BAT burst DATE: 05/11/17 21:52:20 GMT FROM: Scott Barthelmy at NASA/GSFC D. Palmer (LANL), L. Barbier (GSFC), S. Barthelmy (GSFC), L. Cominsky (Sonoma State U.), J. Cannizzo (GSFC-UMBC), J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS), J. Tueller (GSFC) on behalf of the Swift-BAT team: Using the full data set from the recent telemetry downlink, we report further analysis of Swift-BAT GRB 051117A (trigger #164268) (Band, et al., GCN 4280). The ground-analysis position is RA,Dec 228.399,+30.870 {15h 13m 35.7s,+30d 51' 10.3"} (J2000) with an uncertainty of 1.0 arcmin (radius, 90%, stat+sys). T90 is at least 140 +- 10 sec. The partial coding fraction is 72%. The lightcurve has a long FRED-like peak at T-15 sec lasting out to at least T+190 sec. There is a hint of emission peaks at T+225 and T+350 (each ~30 sec in duration). Fitting a simple power law over the interval from T-29 to T+157 sec, the photon index is 1.83 +/- 0.07 with a fluence of at least 4.6 +/- 0.16 X 10^-6 erg/cm^2. The peak flux in a 1-sec wide window starting at T+2.47 sec is 0.93 +/- 0.17 ph/cm^2/sec. All values are in the 15-150 keV band at the 90% confidence level.