TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3134 SUBJECT: GRB 050318: Swift-BAT refined analysis DATE: 05/03/21 22:33:21 GMT FROM: Hans Krimm at NASA-GSFC H. Krimm (GSFC/USRA), S. Barthelmy, L. Barbier (GSFC), J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (GSFC/UMD), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC), G. Sato (ISAS), M. Still (GSFC/USRA), M. Suzuki (Saitama), J. Tueller (GSFC) on behalf of the Swift-BAT team: Continued analysis of the available data for the Swift-BAT GRB 050318 (Krimm, et al., GCN 3111) yields the following additional results. Due to an error in an on-board data processing script, event data from times after T+31.4 seconds were not recorded. Based on analysis of the rate data, we estimate that the lost event data represent about 18 per cent of the total burst flux. The fluence derived from the available event data and scaled to cover the entire burst is 2.1 X 10^-6 erg/cm^2 in the 15-350 keV band. The 1-s peak flux is 3.8 ph/cm^2/s (also 15-350 keV). The photon index of the 1-s peak spectrum (T+28.5 s) is 1.9 +/- 0.12 (90% confidence). The time averaged spectrum yields a photon index of 2.1 +/- 0.11 (90% confidence). The overall measure of burst duration is T90 = 32 +/- 2 s (including systematics).