TITLE: GCN CIRCULAR NUMBER: 35922 SUBJECT: GRB240204A: VIRT optical upper limit DATE: 24/03/14 00:11:58 GMT FROM: Priya Gokuldass at ERAU <gokuldap@my.erau.edu> K. Smith (UVI), P. Gokuldass (ERAU), N. Orange (OrangeWave Innovative Science, LLC), D. Morris (NASA), T. Lombardi (Eckerd College), K. Noonan (UVI), R. Querrard (UVI), D. Smith (UVI) report: We observed the field of GRB240204A (Cenko et al., GCN 35666) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin Islands' Etelman Observatory on 02-05-2024 starting at 00:36:35 (T+10.04 hrs). We performed a series of exposures in an R filter with a total exposure of 4000s. The weather conditions were clear during the hours of observation with an average airmass of 1.08. We do not detect any source within the enhanced XRT position (Beardmore et al. GCN 35671). This non-detection is consistent with the upper limits and detections of the faint optical transient reported by Master (Lipunov et al., GCN 35668), Mondy (Pozanenko et al., GCN 35670), Montarrenti Observatory (Leonini et al., GCN 35672), LCOGT (Perez-Fournon and Poidevin, GCN 35673), Osservatorio Nastro Verde (Ruocco et al., GCN 35677), Liverpool Telescope (Bochenek et al., GCN 35678), and Observatoire de Haute-Provence (Adami et al., GCN 35690). We report the following 3-sigma upper limit: T_mid ||Exposure ||Filter ||Limit T+ 10.04 hrs || 4000s || R || >20.9 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 and NASA EPSCoR award 80NNSC22M0063. R.Q and N.B.O also acknowledge financial support from South Carolina Space Grant award 80NSSC20M0054. This message can be cited. View this GCN Circular online at https://gcn.nasa.gov/circulars/35922. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...