GCN Circular 38611
Subject
GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
Date
2024-12-18T10:05:41Z (22 days ago)
Edited On
2024-12-18T13:59:54Z (22 days ago)
From
Zhanat Maksut at Nazarbayev University <zhanat.maksut@nu.edu.kz>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Zhanat Maksut at Nazarbayev University <zhanat.maksut@nu.edu.kz>
Via
Web form
Z. Maksut (NU), B. Grossan (UCB, NU), T. Komesh (NU), Z. Abdullayev (NU), M. Krugov (FAI) and E. Abdikamalov (NU) 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 241218A, 12 seconds after receipt of an automated GCN / BAT position alert, in Sloan g' and r' bands, with the Burst Simultaneous Three-Channel Imager (Grossan, Kumar & Smoot 2019, JHEA, 32, 14).
We started observations of GRB 241218A (Williams et al., GCN 38601; Strausbaugh et al., GCN 38605) at UT 00:13:43 on 2024-12-18, 292 seconds after the BAT trigger. Observations were made in clear conditions. We report the following upper limit results:
start time t_m-t0(s) end time UL g' UL r' exposure_time (image x s)
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00:26:30 1191 00:29:30 19.51 19.57 3 x 60
The start and end time is in UT. t_m is the middle time, t0 is the BAT trigger time, t_m-t0 is given in seconds. UL gives the 5 sigma upper limit sensitivity in magnitudes, for images co-added to the given exposure time. Calibration was done with 4 Pan-STARRS catalog stars on our images. No color corrections were applied to the values above.
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NU = Nazarbayev University, Astana, Kazakhstan
UCB = University of California, Berkeley, USA
FAI = Fesenkov Astrophysical Institute, Kazakhstan