TITLE: GCN CIRCULAR NUMBER: 14741 SUBJECT: GRB 130603B: Swift-BAT refined analysis DATE: 13/06/03 22:16:10 GMT FROM: Scott Barthelmy at NASA/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), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), A. Melandri (INAF-OAB), D. M. Palmer (LANL), T. Sakamoto (AGU), 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-61 to T+242 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130603B (trigger #557310) (Melandri, et al., GCN Circ. 14735). The BAT ground-calculated position is RA, Dec = 172.222, 17.063 deg, which is RA(J2000) = 11h 28m 53.2s Dec(J2000) = +17d 03' 48.2" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 100%. The mask-weighted light curve shows a single FRED-like spike starting at ~T_0.000, peaking at ~T+0.012 sec, and returning to baseline at~T+0.2sec. There is a smaller pulse ridding on the tail of the initial pulse. T90 (15-350 keV) is 0.18 +- 0.02 sec (estimated error including systematics). The time-averaged spectrum from T+0.01 to T+0.26 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 0.82 +- 0.07. The fluence in the 15-150 keV band is 6.3 +- 0.3 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band is 6.4 +- 0.3 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/557310/BA/