TITLE: GCN CIRCULAR NUMBER: 13333 SUBJECT: GRB 120521C: Swift-BAT refined analysis DATE: 12/05/22 13:27:34 GMT FROM: Scott Barthelmy at NASA/GSFC C. B. Markwardt (GSFC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team): Using the data set from T-240 to T+962 sec from recent telemetry downlinks, we report further analysis of BAT GRB 120521C (trigger #522656) (Baumgartner, et al., GCN Circ. 13318). The BAT ground-calculated position is RA, Dec = 214.288, 42.144 deg, which is RA(J2000) = 14h 17m 09.1s Dec(J2000) = +42d 08' 39.8" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 67%. The mask-weighted light curves shows a FRED peak starting at ~T-2 sec, peaking at ~T+1 sec, abd ending at ~T+40 sec. T90 (15-350 keV) is 26.7 +- 4.4 sec (estimated error including systematics). The time-averaged spectrum from T-1.03 to T+31.84 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.73 +- 0.11. The fluence in the 15-150 keV band is 1.1 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T-0.02 sec in the 15-150 keV band is 1.9 +- 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/522656/BA/