{
  "bibcode": "2025GCN.38830....1O",
  "subject": "GRB 250106A: Swift-XRT observations",
  "submitter": "Phil Evans at U of Leicester <pae9@star.le.ac.uk>",
  "circularId": 38830,
  "eventId": "GRB 250106A",
  "createdOn": 1736174752967,
  "submittedHow": "email",
  "body": "J.P. Osborne (U. Leicester), P. D'Avanzo (INAF-OAB), M.G. Bernardini\n(INAF-OAB), E. Ambrosi\t(INAF-IASFPA) , M. A. Williams (PSU), S.\nDichiara (PSU), J.A. Kennea (PSU), K.L. Page (U. Leicester), A.P.\nBeardmore (U. Leicester) and P.A. Evans (U. Leicester) reports on\nbehalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nSVOM/ECLAIRs-detected burst GRB 250106A (Zhao et al., GCN Circ. 38826),\ncollecting  2.9 ks of Photon Counting (PC) mode data between T0+19.9 ks\nand T0+27.1 ks. \n\nFour uncatalogued X-ray sources have been detected, however none of\nthem is above the RASS limit or shows definitive signs of fading.\nHowever, Source 2 was reported by Qiu et al. (GCN Circ. 38829) to be\nconsistent with the position of a SVOM/VT optical candiate. Details of\nthe Swift-XRT sources are given below:\n\nSource 1:\n  RA (J2000.0):  117.2387  =  07:48:57.28\n  Dec (J2000.0): +63.8123  =  +63:48:44.3\n  Error: 3.0 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: 0.0209 +/- 0.0032 ct s^-1   \n  Distance: 205 arcsec from SVOM/ECLAIRs position.\n  Flux: (5.99 +/- 0.91)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 2:\n  RA (J2000.0):  117.3686  =  07:49:28.47\n  Dec (J2000.0): +63.7079  =  +63:42:28.6\n  Error: 5.9 arcsec (radius, 90% conf.)\n  Count-rate: (5.7 [+2.1, -1.7])e-3 ct s^-1   \n  Distance: 411 arcsec from SVOM/ECLAIRs position.\n  Flux: (4.1 [+1.5, -1.2])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 3:\n  RA (J2000.0):  116.9049  =  07:47:37.18\n  Dec (J2000.0): +63.9115  =  +63:54:41.5\n  Error: 6.5 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: (4.5 [+1.9, -1.5])e-3 ct s^-1   \n  Distance: 642 arcsec from SVOM/ECLAIRs position.\n  Flux: (3.1 [+1.3, -1.0])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 4:\n  RA (J2000.0):  117.2096  =  07:48:50.31\n  Dec (J2000.0): +63.8218  =  +63:49:18.4\n  Error: 7.1 arcsec (radius, 90% conf.)\n  Count-rate: (2.4 [+1.4, -1.0])e-3 ct s^-1   \n  Distance: 207 arcsec from SVOM/ECLAIRs position.\n  Flux: (7.3 [+4.2, -3.1])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021753.\n\nThis circular is an official product of the Swift-XRT team.\n\n"
}