TITLE: GCN CIRCULAR NUMBER: 38023 SUBJECT: GRB 241030B: NUTTelA-TAO / BSTI Optical Limits DATE: 24/11/01 04:57:48 GMT FROM: Toktarkhan Komesh at Nazarbayev University Zh. Abdullayev (NU), Zh. Maksut (NU), T. Komesh (NU), B. Grossan (UCB, NU), D. Berdikhan (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 241030B observing in Sloan g' and r' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14). We started observations at 20:15:59 UT on 2024-10-30, 1.7 h after the BAT trigger. Observations were made in partly cloudy conditions. No source consistent with the XRT (P.A. Evans 2024, GCN Circ. 37983) was detected. We report the following results: start time t-t0(s) end time UL g' UL r' exposure_time (s) -------------------------------------------------------------- 20:15:59 6100 20:16:59 19.2 19.0 60 start time is in UT. t-t0(s) gives the time since trigger, in seconds. UL g' and UL r' give the 5 sigma upper limit sensitivity in magnitudes, for images co-added to the given exposure time. The results in in the table corresponds to co-adds of an initial short exposure image sequence of 0.5 s (these sub-second exposures are read-noise suppressed by our EMCCD cameras, with high gain electron multiplication active). Calibration was done with the 3 bright Pan-STARRS catalog stars on our images. ---------------------------------- NU = Nazarbayev University, Astana, 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.