{
  "bibcode": "2018GCN.23141....1D",
  "body": "V. D'Elia (SSDC) reports on behalf of the Swift/XRT team:\n\nSwift performed a second visit to the field of the  MAXI-detected burst GRB 180809A (Yatabe et al. GCN Circ. 23103). The XRT data comprise 3700 s of exposure time, acquired ~5 days after the GRB trigger and entirely in PC mode. \n\nNo excess is found at the position of the candidate afterglow reported by D'Elia et al. (GCN Circ. 23106), down to a three sigma upper limit of ~4E-3 cts/s, corresponding to a 0.3-10 keV observed flux of ~1E-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum). We thus conclude that the source reported by D'Elia et al. (GCN Circ. 23106) was indeed the X-ray counterpart of the MAXI GRB 180809A.\n\nThis circular is an official product of the Swift/XRT team",
  "circularId": 23141,
  "createdOn": 1534341999000,
  "email": "valerio.delia@ssdc.asi.it",
  "subject": "GRB 180809A: further Swift/XRT observations",
  "submitter": "Valerio D'Elia at ASDC  <valerio.delia@ssdc.asi.it>",
  "eventId": "GRB 180809A"
}