GCN Circular 29937
Subject
GRB 210504A: NOT optical afterglow detection
Date
2021-05-05T00:15:45Z (3 years ago)
From
Daniel Perley at Liverpool JMU <d.a.perley@ljmu.ac.uk>
K. E. Heintz (Univ. of Iceland and DAWN/NBI), D. A. Perley (LJMU), D. B.
Malesani (DTU Space), and A. A. Djupvik (NOT) report on behalf of a
larger collaboration:
We observed the location of the optical and X-ray afterglow of GRB
210504A (Beardmore et al., GCN 29929; Breeveld & Beardmore, GCN 29933)
using the Nordic Optical Telescope (NOT) equipped with the ALFOSC
camera. We obtained 3x300 s frames in the Sloan r-band filter, followed
by 5x200s frames in the z-band filter. Observations were carried out on
2021-05-04 UT between 23:10 and 23:35 (9.3 hours after the BAT trigger
time given by Lien et al. (GCN 29930).
The optical afterglow is detected in the combined images. We report a
refined position (J2000) of:
RA: 14:49:34.04
Dec: -30:32:02.6
No source is visible at this location in Pan-STARRS reference imaging.
The r-band magnitude of the afterglow at the time of the observation is
measured to be 20.95 +/- 0.05.
DisclaimerNone