TITLE: GCN CIRCULAR NUMBER: 9980 SUBJECT: GRB 090929A, Swift-BAT refined analysis DATE: 09/09/30 21:06:52 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), K. Page (U Leicester), D. M. Palmer (LANL), A. M. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team): We report further analysis of Fermi-GBM GRB 090929A (Rau, et al., GCN Circ. 9962). The BAT ground-calculated position is the same as stated in Cummings et al. (GCN Circ. 9966), RA, Dec = 56.494, -5.952 or RA (J2000) 03h 45m 57.9s Dec (J2000) -05d 57' 50" with an estimated 90% containment error radius of 3 arcmin. The partial coding was 73-90% during the burst. The mask-weighted lightcurve shows multiple peaks and spikes, at T+1, T+2, T+4, T+5, and T+10 sec, where T0 is 04:33:07. T90 was 7 +- 2 seconds. The time-averaged spectrum from T0 to T+12 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.96 +- 0.04. The fluence in the 15-150 keV band is 1.69 +- 0.07 x 10^-06 ergs/cm2. The 1-sec peak photon flux measured from T+0.5 sec in the 15-150 keV band is 5.9 +- 0.3 ph/cm2/sec. All the quoted errors are at the 90% confidence level.