TITLE: GCN CIRCULAR NUMBER: 14277 SUBJECT: GRB 130305A BAT refined circular DATE: 13/03/08 22:35:16 GMT FROM: Jay R. Cummings at NASA/GSFC/Swift J. R. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), D. Malesani (DARK/NBI), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU) Using 11 seconds of event data covering part of the burst, we present further analysis of GRB 130305A (Cummings and Palmer, GCN # 14257). This was a ground-detected burst on the edge of the BAT field of view. The best BAT position is RA, Dec 116.774, +52.037, which is: RA (J2000) 07h 47m 05.8s Dec (J2000) 52d 02m 11s with an estimated uncertainty radius of 1.8 arcmin (90% containment). This position is 1.0 arcmin from the XRT afterglow position (Malesani et al, GCN # 14263). The BAT mask-weighted lightcurve does not show more detail than the raw lightcurve due to the extreme partial coding (2.5%). There is a single peak, approximately symmetrical, a total of about 20 seconds long. Note, however, the much longer duration mentioned at high energy by the Konus-Wind team (Golenetskii et al., GCN # 14262. The following spectral results appear to cover about 90% of the total flux of the burst, based on the raw lightcurve excess over constant background. Again, the partial coding makes the uncertainty of the fit parameters large. A fit to a simple power law function has a photon index of 0.78 +/- 0.20. This is harder than most other BAT-detected long GRBs. The fluence from 15-150 keV was (4.8 +/- 1.8) x 10^-6 ergs/cm^2. [GCN OPS NOTE(08mar13): Per author's request, the word "draft" was removed from the Subject-line.]