GCN Circular 37815
Subject
GRB 240727A: VIRT Optical Upper Limit
Date
2024-10-18T16:54:52Z (15 days ago)
From
Priya Gokuldass at ERAU <gokuldap@my.erau.edu>
Via
Web form
K. Smith (UVI), P. Gokuldass (ERAU), N. Orange (OrangeWave Innovative Science, LLC), D. Morris (NASA), T. Lombardi (Eckerd College), F. George (ERAU), K. Noonan (UVI), R. Querrard (UVI), D. Smith (UVI) report:
We observed the field of GRB240727A (Parsotan et al., GCN 36938) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin Islands' Etelman Observatory on 2024-07-30 starting at 2:20:47 (Tmid+71.54 hrs). We performed a series of exposures in an R filter with a total exposure of 1600s. The weather conditions were partly cloudy during the hours of observation with an average airmass of 1.56.
We do not detect any source within the enhanced XRT position (Beardmore et al. GCN 36950). This non-detection is consistent with detections reported by KAIT (Zheng et al., GCN 36939), TRT (Liu et al., GCN 36940), Skynet (Dubay et al., GCN 36941), NOT (An et al., GCN 36962) and SWIFT/UVOT (Kuin et al., GCN 36968) and upper limits reported by Bassano Bresciano (Quadri et al., GCN 36960), JinShan (An et al., GCN 36961), Nastro Verde (Ruocco et al., GCN 36964), MASTER (Lipunov et al., GCN 36969), and MarSEC (Lora et al., GCN 36971). We report the following 3-sigma upper limit:
T_mid ||Exposure ||Filter ||Limit
T+ 71.54 hrs ||1600s || R ||>20.44
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 80NSSC21M001, NASA EPSCoR award 80NNSC22M0063, NSF PAARE award 2319415, and NASA EPSCoR award 80NSSC24M0112. This message can be cited.