GCN Circular 32664
Subject
GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
Event
Date
2022-10-10T16:21:51Z (4 years ago)
From
Filipp Dmitrievich Romanov at Amateur astronomer <filipp.romanov.27.04.1997@gmail.com>
I observed the optical afterglow of the extremely bright GRB 221009A =
Swift J1913.1+1946 (Dichiara et al., GCN Circ. 32632) remotely using
0.61-m f/6.5 Corrected Dall-Kirkham telescope of Burke-Gaffney
Observatory (Lane, 2018, RTSRE, 1, 119) on 2022-10-10. Twelve images
with exposures of 300 seconds and I�� filter were obtained, midtime of
the first image is 02:06:45 UTC (11h56m after the trigger), midtime of
the last image is 03:09:02 UTC (12h58m after the trigger).
I clearly detected the afterglow and measured (aperture photometry,
without deblending) following magnitudes of the afterglow from
comparison to transformed (from Lupton 2005 formula) magnitudes of
nearby stars from the Pan-STARRS DR1 catalogue (Chambers et al.,
2016):
Time (UTC)//Ic magnitude//Error
02:06:45 15.54 0.12
02:12:20 15.60 0.10
02:17:55 15.54 0.11
02:23:29 15.60 0.11
02:29:04 15.64 0.12
02:34:38 15.59 0.11
02:41:08 15.67 0.11
02:46:43 15.69 0.10
02:52:18 15.69 0.11
02:57:53 15.64 0.12
03:03:27 15.70 0.13
03:09:02 15.92 0.13
Magnitudes were not corrected for Galactic extinction.
FITS files available here:
https://observatory.smu.ca/~bgo/sm/id.php?app=0&id=20769 and
https://observatory.smu.ca/~bgo/sm/id.php?app=0&id=20770
Stacked image: https://observatory.smu.ca/~bgo/research/GRB_221009A.jpg
F. D. Romanov (AAVSO member, observer code: RFDA).