TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5146 SUBJECT: GRB 060516: Refined analysis of the Swift-BAT burst DATE: 06/05/16 17:28:26 GMT FROM: Scott Barthelmy at NASA/GSFC D. Hullinger (BYU-Idaho), L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), M. Koss (GSFC/UMD), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/JSPS/USRA), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC) on behalf of the Swift-BAT team: Using the data set from T-119 to T+183 sec from recent telemetry downlinks, we report further analysis of BAT GRB 060516 (trigger #210254) (Parsons, et al., GCN 5144). The BAT ground-calculated position is RA,Dec = 71.167,-18.096 deg {04h 44m 40.8s,-18d 05' 44"} (J2000) +- 3.3 arcmin, (radius, sys+stat, 90% containment). The partial coding was 79%. The ground-calculated image significance in the 15-100 keV band is 12.3 sigma. The mask-weighted lighcurve shows a long relatively smooth burst starting at ~T-30 sec and extending out to T+130, mostly in the 15-50 keV band. There is no significant emission in the >100 keV band. T90 (15-350 keV) is 160 +- 20 sec (estimated error including systematics). The long duration and smooth nature of the lightcurve could be an indication of a high redshift burst. The time-averaged spectrum from T-42.2 to T+134.0 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.15 +- 0.24. The fluence in the 15-150 keV band is 1.1 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+128.56 sec in the 15-150 keV band is 0.3 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. Due to the Sun constraint, this GRB will not be observable by the Swift XRT and UVOT instruments for >31 days.