TITLE: GCN CIRCULAR NUMBER: 17010 SUBJECT: GRB 141031A, Swift-BAT refined analysis DATE: 14/10/31 21:30:21 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings, N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), J. Tueller (GSFC) (i.e. the Swift-BAT team): Using the data set from T-250 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 141031A (trigger #617110) (Gompertz, et al., GCN Circ. 16995). The BAT ground-calculated position is RA, Dec = 128.632, -59.160 deg which is RA(J2000) = 08h 34m 31.6s Dec(J2000) = -59d 09' 36.8" with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 32%. The mask-weighted light curve shows three widely separated peaks. The first is a single symmetric peak from about T-20 to T+20 seconds, the second is another symmetric peak ~20 sec long at about T+800, and the third is two overlapping peaks from about T+850 to T+920 seconds. T90 (15-350 keV) is about 920 +- 10 sec (estimated error including systematics). The time-averaged spectrum from T-22 to T+20 sec is best fit by a simple power-law model with a power law index of 1.21 +- 0.13. The time-averaged spectrum from T+770 to T+920 sec is also best fit by a simple power-law model with a power law index of 1.75 +- 0.18. The total fluence for both intervals in the 15-150 keV band is 2.9 +- 0.5 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from T+5.08 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/617110/BA/