TITLE: GCN CIRCULAR NUMBER: 8447 SUBJECT: GRB 081029: Swift-BAT refined analysis DATE: 08/10/29 12:48:10 GMT FROM: Scott Barthelmy at NASA/GSFC 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), 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): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 081029 (trigger #332931) (Sakamoto, et al., GCN Circ. 8435). The BAT ground-calculated position is RA, Dec = 346.776, -68.179 deg, which is RA(J2000) = 23h 07m 06.3s Dec(J2000) = -68d 10' 43.4" with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 58%. The mask-weighted light curve shows a single relatively smooth peak starting at ~T-50 sec, peaking at ~T+60 sec, and ending at ~T+300 sec. T90 (15-350 keV) is 270 +- 45 sec (estimated error including systematics). The time-averaged spectrum from T-35.6 to T+268.6 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.43 +- 0.18. The fluence in the 15-150 keV band is 2.1 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+52.37 sec in the 15-150 keV band is 0.5 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level. The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/332931/BA/