TITLE: GCN CIRCULAR NUMBER: 10585 SUBJECT: GRB 100413A: Swift-BAT initial refined analysis DATE: 10/04/13 21:07:15 GMT FROM: Scott Barthelmy at NASA/GSFC M. Stamatikos (GSFC/ORAU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), S. T. Holland (CRESST/USRA/GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), J. Tueller (GSFC), T. N. Ukwatta (GWU) (i.e. the Swift-BAT team): Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 100413A (trigger #419404) (Holland, et al., GCN Circ. 10581). The BAT ground-calculated position is RA, Dec = 266.223, 15.833 deg, which is RA(J2000) = 17h 44m 53.4s Dec(J2000) = +15d 50' 00.3" with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 48%. The mask-weighted light curve shows multiple overlapping peaks in two main clusters of peaks. It starts at ~T-45 sec, with the first cluster ending at ~T+40 sec. The second cluster starts around T+90 sec, peaks around T+100 sec, and ends later than T+240 sec. The emission does not return to background between the two clusters. We are issuing this refined circular prior to receiving all the data, because there is a backlog in the downlinking of the data and it will be many hours until receive the data past T+240 sec. These results will be updated when we receive the full data set. Using this partial data set, the time-averaged spectrum from T-1.5 to T+213.1 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.17 +- 0.07. The fluence in the 15-150 keV band is 6.2 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+116.78 sec in the 15-150 keV band is 0.7 +- 0.1 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/419404/BA/