TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4338 SUBJECT: GRB 051211B: Swift XRT confirmation of the afterglow DATE: 05/12/12 13:51:50 GMT FROM: David Burrows at PSU/Swift V. La Parola, V. Mangano (INAF-IASF), C. Pagani (INAF-OAB), and D. N. Burrows (PSU), report on behalf of the Swift XRT team: The Swift XRT began observing GRB 051211B, detected by INTEGRAL (Mereghetti et al., GCN 4327), at 01:05:28 UT on 12 December 2005 (10.8 ks after the burst). With five orbits of data (from 11 ks to 36 ks after the burst), the uncataloged X-ray source reported in Pagani et al. (GCN 4332) is clearly fading, consistent with being the afterglow of this burst. Our updated position is RA 23:2:41.76, Dec 55:04:51.9 (345.6740, 55.0811), which is 29".8 from the INTEGRAL position and 62".9 from the position of the candidate optical afterglow reported in GCN 4328 (Klotz et al.). The lightcurve is initially flat, with a steep power law decay commencing about 20 ks after the burst. Observations are continuing. Refined analysis, including decay indices and spectral results, will be issued in a further circular after accumulation of several more orbits of data.