TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4973 SUBJECT: GRB060418: Swift XRT Team Refined Analysis DATE: 06/04/18 12:05:19 GMT FROM: Abe Falcone at PSU/Swift A. D. Falcone, D. N. Burrows, Jamie Kennea (PSU), report on behalf of the Swift XRT team: Following the Malindi gap, we have analyzed the initial Swift XRT data from GRB 060418 (Falcone et al., GCN4966), with a total exposure of 1.4 ks. The refined XRT position is: RA(J2000) = 15 45 42.4 Dec(J2000) = -03 38 22.8 We estimate an uncertainty of 4 arcseconds radius (90% containment). In addition to the afterglow decay, the early light curve has bright flaring. The largest flare has a peak of about 460 c/s at approximately 128 s after the trigger time. Aside from the flaring, the light curve is clearly fading, but the rate is difficult to estimate due to the flaring and the limited data available at this time. A preliminary estimate of the power law decay index is approximately 0.6 ± 0.3. This Circular is an official product of the Swift XRT Team.