[vsnet-grb-info 28165] GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  30268
SUBJECT: GRB 210619B: SARA-KP 0.9m Optical Afterglow Detection
DATE:    21/06/20 08:18:35 GMT
FROM:    Kyle Pellegrin at Clemson University  <pelleg2 at g.clemson.edu>

K. Pellegrin, S. Anandagoda, and D. Hartmann report:

We observed the field of GRB 210619B detected by Swift BAT (D’Avanzo et al.,
GCN #30261), Global MASTER-Net (Lipunov et al., GCN #30262), GECAM (Zhao et
al., GCN #30264), iTelescope (Kong, GCN #30265), and Ondrejov D50 (M.
Jelinek et al., GCN #30263) using the SARA 0.9m optical telescope located
at Kitt Peak, AZ, USA, equipped with the Alta-E6-1105 camera.

Observation started at 05:19:14 UTC on 2021-06-20 and ended at 06:13:23 UTC
on 2021-06-20. We obtained a series of 60s exposure frames in the
Johnson-Cousins R filter. We detect the optical afterglow of GRB 210619B at
the enhanced Swift-XRT position (Beardmore, et al., GCN #30267).

The estimated magnitude of the GRB afterglow was found by stacking 20
images of 60s each in the Johnson-Cousins R band filter. The GRB was
visible in each of the stacked images.

T_start-T0 (hrs)   T_end-T0 (hrs)     Start Date (UTC) Filter Magnitude
(mag)

----------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------

5.32 5.70          2021-06-20T05:19:14        R      18.51

5.73 6.22   2021-06-20T05:43:59   R             18.77


Photometry is done based on the PanSTARRS catalog.

The Southeastern Association for Research in Astronomy (SARA) consortium
operates three telescopes: the 0.9-m SARA-KP at Kitt Peak in Arizona, and
the 0.6-m SARA-CT at Cerro Tololo in Chile, and the 1.0-m SARA-RM (formerly
the JKT) telescope at Roque de los Muchachos Observatory in the Canary
Islands. For more information see: Keel et al. (2016):
https://iopscience.iop.org/article/10.1088/1538-3873/129/971/015002

---------------------------------------------------------------------------------------