TITLE: GCN CIRCULAR NUMBER: 31486 SUBJECT: GRB 220117B: Swift-BAT refined analysis DATE: 22/01/18 15:36:36 GMT FROM: Amy Lien at GSFC T. Parsotan (GSFC/UMBC), S. D. Barthelmy (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+717 sec from the recent telemetry downlink, we report further analysis of BAT GRB 220117B (trigger #1093611) (Melandri et al., GCN Circ. 31468). The BAT ground-calculated position is RA, Dec = 191.989, -28.762 deg which is RA(J2000) = 12h 47m 57.3s Dec(J2000) = -28d 45' 42.8" with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 96%. The mask-weighted light curve shows a weak structure that starts at ~T-3 s and ends at ~T+23 s. T90 (15-350 keV) is 24.37 +- 4.63 sec (estimated error including systematics). The time-averaged spectrum from T-2.73 to T+23.29 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.94 +- 0.32. The fluence in the 15-150 keV band is 2.9 +- 0.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.13 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/1093611/BA/