{
  "bibcode": "2021GCN.29829....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 210419A (Laha, et al., GCN 29828) with the LCO 1-m Sinistro instrument at the Siding Spring Observatory, Australia site, on April 19, from 08:33 to 08:57 UT (corresponding to 1.67 to 2.1 hours from the GRB trigger time) with the Bessel R and I filters.\n\nWe performed a series of 4x180s exposures in R and I. We do not detect any uncatalogued optical source in the coadded images within the XRT error region (Laha, et al., GCN 29828).  Using the USNO-B.1 catalog as reference, we calculate the following upper limits:\n\nR>21.91\n\nI>21.16\n\nThese magnitudes are not corrected for galactic extinction.\n\nR.S. is funded by NSF AST grant #1831682",
  "circularId": 29829,
  "createdOn": 1618846831000,
  "email": "robert.strausbaugh@uvi.edu",
  "subject": "GRB 210419A: LCO Optical Upper Limit",
  "submitter": "Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh@uvi.edu>",
  "eventId": "GRB 210419A"
}