TITLE: GCN CIRCULAR NUMBER: 15769 SUBJECT: GRB 140129A, Swift-BAT refined analysis DATE: 14/01/29 17:40:59 GMT FROM: Amy Lien at GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (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 140129A (trigger #585128) (Melandri, et al., GCN Circ. 15760). The BAT ground-calculated position is RA, Dec = 37.851, -1.594 deg which is RA(J2000) = 02h 31m 24.2s Dec(J2000) = -01d 35' 40.1" with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 57%. The mask-weighted light curve shows a single peak structure starts at ~T+1.2 s, peaks at ~T+2.5 s, and ends at ~ T+4.6 s. T90 (15-350 keV) is 2.99 +- 0.79 sec (estimated error including systematics). The time-averaged spectrum from T+1.25 to T+4.62 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 2.08 +- 0.33. The fluence in the 15-150 keV band is 1.3 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+1.91 sec in the 15-150 keV band is 0.9 +- 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/585128/BA/