{
  "circularId": 40027,
  "submittedHow": "web",
  "createdOn": 1743696079742,
  "format": "text/plain",
  "subject": "GRB 250402A: Swift-XRT observations",
  "body": "S. Dichiara (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB), K.L. \nPage and P.A. Evans (U.Leicester) reports on behalf of the Swift-XRT team:\n\nWe have analysed 2.4 ks of XRT data for the SVOM/ECLAIRs-detected burst\nGRB 250402A (SVOM trigger sb25040203; Chen et al., GCN circ. 40014), from \nT0+49.2 ks to T0+51.5 ks after the  SVOM/ECLAIRs trigger. The data are \nentirely in Photon Counting (PC) mode.\n\nWe find an uncatalogued X-ray source consistent with the X-ray counterpart \nidentified by SVOM/MXT (Maggi et al., GCN circ. 40019) and the optical \ncounterpart (Xin et al., GCN 40015, Pérez-Fournon et al., GCN 40020, \nSchneider et al., GCN 40022, Magnani et al., GCN 40023). We note that the \nsource is fading compared to the flux reported by previous MXT observations \n(Maggi et al., GCN circ. 40019). \nDetails of this source are given below:\n\nSource 1:\n  RA (J2000.0):  213.4089  =  14:13:38.13\n  Dec (J2000.0): -5.9302  =  -05:55:48.5\n  Error: 3.4 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate:0.045 (±0.012) ct s-1   \n  Flux: 1.9 (±0.5) ×10-12 erg cm-2 s-1 (observed, 0.3-10 keV)\n\nThis XRT position is 1.07 arcsec away from the optical position.\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/SVOM/SVOM_FIELD00009/.\n\nThis circular is an official product of the Swift-XRT team.",
  "bibcode": "2025GCN.40027....1D",
  "eventId": "GRB 250402A",
  "submitter": "Simone Dichiara at Pennsylvania State University <sbd5667@psu.edu>"
}