GCN Circular 25952
Subject
GRB 191004A: NOT optical upper limits
Date
2019-10-05T03:47:35Z (5 years ago)
From
Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI <keh14@hi.is>
K. E. Heintz (Univ. of Iceland), D. B. Malesani (DTU space), and S. Moran (NOT), report on behalf of a larger collaboration:
We observed the field of the Swift-detected GRB 191004A (Cenko et al., GCN 25945) with the Nordic Optical Telescope (NOT) equipped with StanCAM. We obtained 3x300s exposures with the Bessel R filter starting at 02:10:34 UT on October 5 (i.e. 8.05 hr post-burst). We do not detect the previously reported optical afterglow (Cenko et al., GCN 25945; Lipunov et al., GCN 25944), down to a limit of R > 23.5 mag, calibrated against the photometry of nearby field stars from the USNO-B1 catalog.