[vsnet-grb-info 27758] GRB 210420B: KAIT Optical Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29861
SUBJECT: GRB 210420B: KAIT Optical Observations
DATE:    21/04/21 14:39:40 GMT
FROM:    Weikang Zheng at UC Berkeley  <weikang at berkeley.edu>

WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on

behalf of the KAIT GRB team:


The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at

Lick Observatory, responded to the Swift GRB 210420B (Moss et al.,

GCN 29844) starting at ~0.61 days after the Swift trigger (Lien et al.

GCN 29854). A total of 30x60s images were obtained in the clear (roughly R)

filters. We detect the optical afterglow (Lipunov et al., GCN 29845;
Oksanen,

GCN 29846; Hu et al., GCN 29847; Sun et al., GCN 29848; Leonini et al.,

GCN 29851; de Ugarte Postigo et al., GCN 29852; Watson et al., GCN 29858)

in the coadd image with a mag of 19.9 +/- 0.2, calibrated to the

Pan-STARRS1 catalog.