TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5595 SUBJECT: GRB 060923B, Swift-BAT refined analysis DATE: 06/09/23 16:16:00 GMT FROM: Scott Barthelmy at NASA/GSFC L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC) on behalf of the Swift-BAT team: Using the data set from T-240 to T+754 sec from recent telemetry downlinks, we report further analysis of BAT GRB 060923B (trigger #230702) (Stamitikos, et al., GCN Circ. 5590). The BAT ground-calculated position is RA,Dec = 238.193, -30.907 deg {15h 52m 46.3s, -30d 54' 25.8"} (J2000) +- 1.6 arcmin, (radius, sys+stat, 90% containment). The partial coding was 36%. The mask-weighted lightcurve has a single peak starting at T-1 sec and ending at T+10 sec. T90 (15-350 keV) is 8.8 +- 0.1 sec (estimated error including systematics). The time-averaged spectrum from T-0.1 to T+9.9 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.53 +- 0.25. The fluence in the 15-150 keV band is 4.8 +- 0.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+4.93 sec in the 15-150 keV band is 1.5 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.