TITLE: GCN CIRCULAR NUMBER: 43388 SUBJECT: GRB 260111A: Swift-XRT observations DATE: 26/01/13 11:01:35 GMT FROM: Phil Evans at U of Leicester <pae9@star.le.ac.uk> S. Lanava (PSU), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), M. Perri (SSDC & INAF-OAR), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), S. Dichiara (PSU), J.A. Kennea (PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Swift/BAT-GUANO (Ronchini et al., GCN 43377) and Fermi/GBM (Fermi GBM team, GCN 43370; Palafox et al., GCN 43384) detected burst GRB 260111A, collecting 2.8 ks of Photon Counting (PC) mode data between T0+94.3 ks and T0+104.8 ks. One uncatalogued X-ray source has been detected within the estimated 3-sigma Swift/BAT error region (493 arcsec), it is below the RASS limit and shows no definitive signs of fading. A source consistent with the position of XRT source 2 has been reported in the optical with COLIBRÍ, suggesting it could be the GRB afterglow (Ducoin et al., GCN 43386). Details of this source are given below: Source 2: RA (J2000.0): 229.5858 = 15h 18m 20.60s Dec (J2000.0): +51.9736 = +51d 58' 24.8" Error: 6.3 arcsec (radius, 90% conf.) Count-rate: (5.6 [+2.4, -1.9])e-3 ct s^-1 Distance: 27 arcsec from Swift/BAT position. Flux: (1.56 [+0.66, -0.53])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) A catalogued source was also detected within the estimated 3-sigma Swift/BAT error region (493 arcsec). The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/ToO_GRBs/00021897. This circular is an official product of the Swift-XRT team. View this GCN Circular online at https://gcn.nasa.gov/circulars/43388. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...