GCN Circular 30748
Subject
GRB 210901A: LCO Optical Upper Limit
Date
2021-09-01T20:02:31Z (4 years ago)
From
Robert Strausbaugh at U. of the Virgin Islands <robert.strausbaugh@uvi.edu>
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:
We observed Swift GRB 210901A (Laha, et al., GCN 30746) with the LCO 1-m Sinistro instrument at the South African Astronomical Observatory site, on September 1, from 17:14 to 17:36 UT (corresponding to 2.17 to 2.53 hours from the GRB trigger time) with the Bessel R and I filters.
We performed a series of 3x300s exposures in R and I. In the XRT detection region (Laha, et al., GCN 30746) no optical counterpart could be detected down to the following upper limits, calculated using the USNO-B.1 catalog as reference:
R>21.55
I>21.16
These magnitudes are not corrected for galactic extinction.
R.S. is funded by NSF AST grant #1831682