TITLE: GCN CIRCULAR NUMBER: 38830 SUBJECT: GRB 250106A: Swift-XRT observations DATE: 25/01/06 14:45:52 GMT FROM: Phil Evans at U of Leicester J.P. Osborne (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. A. Williams (PSU), S. Dichiara (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the SVOM/ECLAIRs-detected burst GRB 250106A (Zhao et al., GCN Circ. 38826), collecting 2.9 ks of Photon Counting (PC) mode data between T0+19.9 ks and T0+27.1 ks. Four uncatalogued X-ray sources have been detected, however none of them is above the RASS limit or shows definitive signs of fading. However, Source 2 was reported by Qiu et al. (GCN Circ. 38829) to be consistent with the position of a SVOM/VT optical candiate. Details of the Swift-XRT sources are given below: Source 1: RA (J2000.0): 117.2387 = 07:48:57.28 Dec (J2000.0): +63.8123 = +63:48:44.3 Error: 3.0 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: 0.0209 +/- 0.0032 ct s^-1 Distance: 205 arcsec from SVOM/ECLAIRs position. Flux: (5.99 +/- 0.91)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 2: RA (J2000.0): 117.3686 = 07:49:28.47 Dec (J2000.0): +63.7079 = +63:42:28.6 Error: 5.9 arcsec (radius, 90% conf.) Count-rate: (5.7 [+2.1, -1.7])e-3 ct s^-1 Distance: 411 arcsec from SVOM/ECLAIRs position. Flux: (4.1 [+1.5, -1.2])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 3: RA (J2000.0): 116.9049 = 07:47:37.18 Dec (J2000.0): +63.9115 = +63:54:41.5 Error: 6.5 arcsec (radius, 90% conf. [Enhanced position]) Count-rate: (4.5 [+1.9, -1.5])e-3 ct s^-1 Distance: 642 arcsec from SVOM/ECLAIRs position. Flux: (3.1 [+1.3, -1.0])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV) Source 4: RA (J2000.0): 117.2096 = 07:48:50.31 Dec (J2000.0): +63.8218 = +63:49:18.4 Error: 7.1 arcsec (radius, 90% conf.) Count-rate: (2.4 [+1.4, -1.0])e-3 ct s^-1 Distance: 207 arcsec from SVOM/ECLAIRs position. Flux: (7.3 [+4.2, -3.1])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV) 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/00021753. This circular is an official product of the Swift-XRT team.