[vsnet-grb-info 27769] GRB 210420B: Montarrenti Observatory follow-up observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29872
SUBJECT: GRB 210420B: Montarrenti Observatory follow-up observations
DATE:    21/04/21 21:17:34 GMT
FROM:    Simone Leonini at Monarrenti Obs  <s.leonini at iol.it>

Simone Leonini, M. Conti, P. Rosi and L.M. Tinjaca Ramirez (Montarrenti Observatory, Siena, Italy) report:

In reference to the GRB 210420B (Moss, et al., GCN 29844), as a follow-up of our early observations already reported in GCN 29851, we kept on imaging the afterglow until 2021-04-21 02:49:13 UT with the same conditions, set-up and analysis. Here our complete set of measurements:

2021 Apr 20.99207 UT (23:48:35 mid-time) R=19.0 +/-0.13
2021 Apr 21.03089 UT (00:44:29 mid-time) R=19.2 +/-0.14
2021 Apr 21.06793 UT (01:37:49 mid-time) R=19.1 +/-0.14
2021 Apr 21.11587 UT (02:46:51 mid-time) R=19.5 +/-0.12

Along the span of our observations we estimate from our measurements a decay rate of 1.02+/-0.35.