{
  "format": "text/plain",
  "subject": "GRB 250317B: Swift-XRT observations",
  "body": "A. Melandri (INAF-OAR), V. D'Elia (SSDC & INAF-OAR), E. Ambrosi, A. D'Ai (INAF-IASFPA) , J.A. Kennea (PSU) and P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the SVOM/ECLAIRs GRB 250317B (Zhao et al., GCN circ. 39752 and GCN circ. 39753) and SVOM/MXT (Götz et al., GCN circ. 39756), collecting  1.7 ks of Photon Counting (PC) mode data between T0+10.0 ks and T0+12.9 ks (SVOM burst-id sb25031701). \n\nOne uncatalogued X-ray source has been detected within the estimated 3-sigma SVOM/MXT error region (Götz et al., GCN circ. 39756), consistent with the optical counterpart (Watson et al., GCN 39754). The source is fading with 3.0-σ significance. Details of this source are given below:\n\nSource 1:\n  RA (J2000.0):  211.6427  =  14:06:34.3\n  Dec (J2000.0): +40.0796  =  +40:04:46.7\n  Error: 3.0 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: 0.19 (±0.04) ct s-1   \n  Flux: 3.7 (±0.4) ×10-12 erg cm-2 s-1 (observed, 0.3-10 keV)\n\nThe 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/SVOM/SVOM_FIELD00003/.\n\nThis circular is an official product of the Swift-XRT team.",
  "bibcode": "2025GCN.39763....1M",
  "createdOn": 1742223953001,
  "submitter": "Andrea Melandri at INAF-OAR <andrea.melandri@inaf.it>",
  "eventId": "GRB 250317B",
  "submittedHow": "web",
  "circularId": 39763
}