GCN Circular 31795
Subject
GRB 220325A: LCO Optical Upper Limits
Date
2022-03-26T13:24:25Z (2 years ago)
From
Robert Strausbaugh at U. of the Virgin Islands <robert.strausbaugh@uvi.edu>
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:
We observed Swift GRB 220325A (Ferro et al., GCN 31787) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on March 26, from 09:25 to 09:53 UT (corresponding to 16.15 to 16.62 hours from the GRB trigger time) with the Bessel R and I filters.
We performed a series of 3x300s exposures in I and R bands. We do not detect an optical counterpart within the XRT enhanced error region (Osborne et al., GCN 31790) in either band, consistent with other non-detections (Lipunov et al., GCN 31773; Gupta et al., GCN 31793). The following upper limits are calculated using the USNO-B.1 catalog as reference:
R>21.08
I>20.14
These magnitudes are not corrected for galactic extinction.
R.S. is funded by NSF AST grant #1831682