{
  "bibcode": "2021GCN.30769....1S",
  "body": "R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:\n\nWe observed Swift GRB 210905A (Sonbas, et al., GCN 30765) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on September 5, from 01:09 to 01:36 UT (corresponding to 0.95 to 1.40 hours from the GRB trigger time) with the Bessel R and I filters.\n\nWe performed a series of 3x300s exposures in R and I. In the XRT detection region (Sonbas, et al., GCN 30765) we detect an uncatalogued source in I band at the following coordinates (309.0481637, -44.4402618).  Using the USNO-B.1 catalog as reference, we calculate the following magnitudes and upper limits:\n\nR>22.44\n\nI=19.52+/-0.09\n\nThese magnitudes are not corrected for galactic extinction.  The detection in I and the lack of detection in R is suggestive of a high-z source.  As such additional follow-up is encouraged.  Additional LCO measurements are underway.\n\nR.S. is funded by NSF AST grant #1831682",
  "circularId": 30769,
  "createdOn": 1630810850000,
  "email": "robert.strausbaugh@uvi.edu",
  "subject": "GRB 210905A: LCO Optical Detection",
  "submitter": "Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>",
  "eventId": "GRB 210905A"
}