[vsnet-grb-info 25174] GRB 200228B: LCO Optical Upper Limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27274
SUBJECT: GRB 200228B: LCO Optical Upper Limit
DATE:    20/03/01 11:29:15 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh at 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 200228B (Laha et al., GCN 27254) with the LCO 1-m Sinistro instrument at the McDonald Observatory, Texas, USA site, on February 29, from 10:52 to 11:42 UT (corresponding to 23.4 to 24.5 hours after the GRB trigger time) with the Bessel I and R filters.

We performed a series of 10x120s exposures in I and R. We do not detect any uncatalouged sources in the individual frames (nor in stacked images) in the Swift error region.  Using the USNO-B.1 catalog as reference, we obtain the following 3-sigma upper limits in stacked images:

R > 22.08

I > 20.77

R.S. is funded by NSF AST grant #1831682