TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4229 SUBJECT: GRB051109A: further steepening in the X-ray light curve DATE: 05/11/09 16:49:51 GMT FROM: Sergio Campana at INAF-OAB S. Campana (INAF-OAB), T. Mineo (INAF-IASFPA), G. Tagliaferri (INAF-OAB), V. Mangano (INAF-IASFPA), P. Romano (INAF-OAB) on behalf of the Swift/XRT team: After the analysis of the full initial dataset, we see that the light curve of GRB051109A shows a further break besides the one already highlighted previously (Campana et al., GCN 4228). This second break is relatively unconstrained occurring between the first (<200 s) and the second (>3000 s) Swift orbit. In the first part the decay is very steep with index alpha_1=-3.1 +/- 0.6 (90% containment, as reported). The second power law contains basically no data and it is only loosely constrained. The third power law has alpha_3=-1.2 +/- 0.1. The reduced chi2 is 1.2 (57 dof). The expected flux at 1 day is 8e-13 erg cm^-2 s^-1. [GCN_OPS_NOTE(09nov05): Per author's request, the Subject line was changed from "050911A" to "051109A".]