GCN Circular 43149
Subject
GRB 251214B: VIRT Optical Upper Limit
Event
Date
2025-12-18T16:23:01Z (19 hours ago)
From
Priya Gokuldass at ERAU <gokuldap@my.erau.edu>
Via
Web form
P. Gokuldass (ERAU), F. George (UVI), N. Orange (OrangeWave Innovative Science, LLC), B. Gendre (UVI), D. Morris (NASA), and T. Lombardi (Eckerd College) report:
We observed the field of long GRB 251214B detected by Fermi (Fermi team, GCN 43088), Swift (Eyles-Ferris et al., GCN 43089; Kuin and Eyles-Ferris, GCN 43105; Burrows et al., GCN 43112), and GECAM-B (Luo et al., GCN 43113) with the 0.5m Virgin Island Robotic Telescope (VIRT) at the University of the Virgin Islands' Etelman Observatory on 2025-12-14 starting at 23:12:24.856 UTC (T-mid ~ T0 + ~15h). We performed a series of exposures in an R filter with a total exposure of 1210s. The weather conditions were partly cloudy during the hours of observation with an average airmass of 2.06.
We do not detect any source at the enhanced XRT position reported (Evans et al., GCN 43098). This non-detection is consistent with reported detections (Eyles-Ferris et al., GCN 43089; Kang et al., GCN 43093; Gress et al., GCN 43095; Fu et al., GCN 43097; Gupta et al., GCN 43100; Watson et al., GCN 43103; Kuin and Eyles-Ferris, GCN 43105; Pérez-Fournon et al., GCN 43123, de Ugarte Postigo et al., GCN 43131) and upper limits (Volnova et al., GCN 43124; Pankov et al., GCN 43132; Volnova et al., GCN 43141; Lin et al., GCN 43134).
We report the following 3-sigma upper limit:
T_mid ||Exposure ||Filter ||Limit
T+ ~15h || 1210s || R || > 20.4
The limit is estimated from comparison to nearby Gaia D3 synphot stars and is not corrected for Galactic extinction. We acknowledge the use of STDWeb interface to verify our result.
We acknowledge financial support in part from NASA EPSCoR 80NNSC22M0063, NSF AST 2319415, and NASA EPSCoR 80NSSC24M0112. This message can be cited.