GCN Circular 32976
Subject
GRB 221120A: VIRT Optical Upper Limit
Date
2022-11-23T18:55:14Z (a year ago)
From
Priyadarshini Gokuldass at U. of the Virgin Islands <priyadass.94@gmail.com>
R. Querrard (UVI), P. Gokuldass (Florida Institute of Technology), N.
Orange (OrangeWave Innovative Science, LLC), K. Noonan (UVI), K. Smith
(UVI), D. Morris (UVI) report:
We observed the field of GRB221120A (R. A. J. Eyles-Ferris et al., GCN
32955) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the
University of the Virgin Islands' Etelman observatory on 11-21-2022
starting at 01:20:09 UT (T+3.8 hrs). We performed a series of exposures in
the R filter with a total exposure of 4000 s. The weather conditions were
partly cloudy to cloudy during the hours of observation with an average
airmass of 1.1.
We detect no new source within the enhanced XRT position error circle (Goad
et al., GCNC 32962) consistent with other non-detections (Swain et al., GCN
32956, O'Connor
et al., GCN 32957, Leonini et al. GCN 32961, Gompertz et al, GCN 32966; and
Odeh et al., GCN 32968) and report the following 5-sigma upper limit:
T_mid ||Exposure ||Filter ||Limit
T+ 4.3 hrs ||4000s ||R ||>20.34
The limit is estimated from comparison to nearby USNO B1 stars and is not
corrected for Galactic extinction. The VIRT is still in the commissioning
phase.
We acknowledge financial support from NASA MUREP MIRO award 80NSSC21M0001,
NASA EPSCoR award 80NSSC22M0063, and NSF EiR award 1901296. R.Q. and N.B.O.
also acknowledge financial support from South Carolina Space Grant award
80NSSC20M0054. This message can be cited.