TITLE: GCN CIRCULAR NUMBER: 12201 SUBJECT: GRB 110726A: Swift-BAT refined analysis DATE: 11/07/26 11:38:19 GMT FROM: Scott Barthelmy at NASA/GSFC J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU), C. A. Wolf (PSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+572 sec from the recent telemetry downlink, we report further analysis of BAT GRB 110726A (trigger #458059) (Wolf, et al., GCN Circ. 12196). The BAT ground-calculated position is RA, Dec = 286.713, 56.070 deg which is RA(J2000) = 19h 06m 51.2s Dec(J2000) = +56d 04' 11.0" with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a single peak starting at ~T-1 sec, peaking at ~T+2 sec, and ending at ~T+5 sec. T90 (15-350 keV) is 5.2 +- 1.1 sec (estimated error including systematics). The time-averaged spectrum from T-0.9 to T+5.0 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.64 +- 0.87, and Epeak of 46.5 +- 11.8 keV (chi squared 79.8 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.2 +- 0.3 x 10^-7 erg/cm2 and the 1-sec peak flux measured from T+0.61 sec in the 15-150 keV band is 1.0 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.86 +- 0.18 (chi squared 87.7 for 57 d.o.f.). 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/458059/BA/