TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4518 SUBJECT: GRB 060115: Refined analysis of the Swift-BAT burst DATE: 06/01/16 00:52:07 GMT FROM: Scott Barthelmy at NASA/GSFC L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), K. Hurley (Berkeley), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), J. Norris (GSFC), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS), J. Tueller (GSFC) on behalf of the Swift-BAT team: Using the downloaded data set from T-300 to T+302 sec from recent telemetry downlinks, we report further analysis of BAT GRB 060115 (trigger #177408) (Tagliaferri, et al., GCN 4509). The BAT ground-calculated position is (RA,Dec) = 54.005,+17.336 deg {03h 36m 01.1s,+17d 20' 10.5"} (J2000) +- 2.0 arcmin, (radius, sys+stat, 90% containment). This is 1.7 arcmin from the position reported by the XRT (Perri, et al. GCN 4514). The partial coding was 85%. The lightcurve consists of faint precursor peak starting at T-50 sec, peaking around T-30sec, and merging into the second peak. The second peak is roughly triangular in shape, starting at T-15 sec, peaking at T+5sec, and ending at T+40 sec. There is a third and largest peak (also roughly triangular in shape) starting at T+80 sec, peaking at T+95 sec, and ending at T+120 sec. T90 (15-350 keV) is at least 142 +- 5 sec (estimated error including systematics). The power law index of the time-averaged spectrum is 1.76 +- 0.12. The fluence in the 15-150 keV band is (1.9 +- 0.1) x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+94.71 sec in the 15-150 keV band is (0.9 +- 0.1) ph/cm2/sec. A cut-off power law model is a marginally better fit to the data. The power law index is 1.0 +/- 0.5 and Epeak is 62 (+31)(-10) keV; the total fluence is (1.8 +/- 0.2) x 10^-6 erg/cm2 and the peak flux is (0.9 +/- 0.1) ph/cm2/sec. All the quoted errors are at the 90% confidence level.