{
  "bibcode": "2022GCN.31357....1P",
  "body": "D. A. Perley (LJMU) reports:\n\nWe acquired multicolor imaging of the optical afterglow of GRB 220101A\n(Tohuvavohu et al., GCN 31347) using the IO:O camera of the 2m robotic\nLiverpool Telescope.  The afterglow was observed twice in the griz\nfilters on 2022-01-01 UT, with the first epoch taking place between\n20:07 and 20:17 and the second between 21:21 and 21:31.\n\nPhotometry with reference to SDSS secondary standard stars in\nthe field gives the following magnitudes:\n\ndt(d)   filter mag   unc\n0.6236  g      21.97 0.10\n0.6254  r      19.84 0.03\n0.6271  i      18.48 0.03\n0.6288  z      18.20 0.03\n0.6749  g      22.21 0.13\n0.6767  r      19.92 0.03\n0.6784  i      18.58 0.03\n0.6802  z      18.27 0.03\n\nMagnitudes are given in the SDSS system and uncorrected for extinction. \nTimes are referenced to the BAT trigger time.\n\nThe colors are consistent with a moderately high-redshift (z = 4-5) \nafterglow, in agreement with the result of Fu et al. (GCN 31353).\n\n\n\n\n\nDisclaimerNone",
  "circularId": 31357,
  "createdOn": 1641075253000,
  "email": "d.a.perley@ljmu.ac.uk",
  "subject": "GRB 220101A: Liverpool telescope imaging of a high-redshift afterglow",
  "submitter": "Daniel Perley at Liverpool JMU  <d.a.perley@ljmu.ac.uk>",
  "eventId": "GRB 220101A"
}