GCN Circular 32896
Subject
GRB 221028A: NUTTelA-TAO / BSTI Early Optical Limits
Date
2022-10-31T02:35:10Z (2 years ago)
From
Toktarkhan Komesh at Nazarbayev University <toktarkhan.komesh@nu.edu.kz>
T. Komesh (NU), B. Grossan (UCB, NU), Z. Maksut (NU), M. Krugov (FAI),
report on behalf of the Energetic Cosmos Laboratory: The Nazarbayev
University Transient Telescope at Assy-Turgen Astrophysical Observatory
(NUTTelA-TAO) observed the field of GRB 221028A on receipt of an
automated GCN / BAT position alert, observing in Sloan g', r' and i'
bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan,
Kumar & Smoot 2019, JHEA, 32, 14).We started observations at UT
2022-10-28 13:47:19, 1852 s after the BAT trigger. Observations were
made under partially cloudy conditions, beginning with the target at an
altitude of 82 deg. No new or changing sources consistent with the XRT
position (Lien 2022, GCN 32874) were detected. Note that these
observations provide essentially full-time coverage, simultaneous in all
three bands. We report the following results: start time t-t0(s) end
time UL g' UL r' ULi' exposure_time (s) ------------ --------
----------- ------ ------ ----- ------ 13:47:19 1852 13:48:19 19.3 18.9
18.7 60 13:48:19 1912 13:58:19 20.3 19.4 20.0 600 start time is in UT.
t-t0(s) gives the time since trigger, in seconds. UL gives the 5 sigma
upper limit sensitivity in magnitudes for an image withindividual
exposure time (first row) and for images co-added to the given exposure
time (second row).��The given upper limit values are derived from the
average calibration with only 2-4 standard stars per co-added frame, and
no other analysis or corrections. ---------------------------------- NU
= Nazarbayev University, Nur-Sultan, Kazakhstan UCB = University of
California, Berkeley, USA FAI = Fesenkov Astrophysical Institute,
Kazakhstan This research has been funded by the Science Committee of the
Ministry of Science and Higher Education of the Republic of Kazakhstan
(Grant No. AP14870504). The NUTTelA-TAO Team acknowledges the support of
the staff of the Assy-Turgen Astrophysical Observatory, Almaty,
Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazkhstan.