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GCN Circular 35180

GRB230506B: VIRT optical upper limit
2023-11-24T20:33:20Z (3 months ago)
Priya Gokuldass at ERAU <>
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K. Noonan (UVI), P. Gokuldass (ERAU), N. Orange (OrangeWave Innovative Science, LLC), D. Morris (NASA), K. Smith (UVI), R. Querrard (UVI), T. Lombardi (Eckerd College)

We observed the field of GRB230506B (Dichiara et al. GCN 33727) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin Islands' Etelman Observatory on 05-07-2023 starting at 05:20:40.065 (T+16.33 hrs). We performed a series of exposures in R filter with a total exposure of 3860 s. The weather conditions were clear during the hours of observation with an average airmass of ~2.6.

We do not detect an uncatalogued source within the Swift-XRT error region and report the following 3-sigma upper limit: 

T_mid     ||Exposure ||Filter ||Limit 
T+17 hrs ||3860s     ||R        ||>20.1 

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.
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