TITLE: GCN CIRCULAR NUMBER: 43732 SUBJECT: EP260213a: NUTTelA-TAO Early Optical Limits DATE: 26/02/14 10:20:16 GMT FROM: Zhanat Maksut at Nazarbayev University <zhanat.maksut@nu.edu.kz> Z. Maksut (NU), T. Komesh (NU), D. Berdikhan (NU), E. Abdikamalov (NU), M. Krugov (FAI), K. Baigarin (NU), M. Coughlin (UMN), P. Hello (IJCLAB), S. Antier (IJCLAB), and S. Karpov (FZU) on behalf of the GRANDMA/NUTTelA-TAO: The Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) pointed at EP 260213a on receipt of an automated GCN / EP position alert, observing in Sloan g' and i' bands, with the Burst Simultaneous Three-Channel Imager (BSTI; Grossan, Kumar & Smoot 2019, JHEA, 32, 14). We started observations at 20:05:22 UT on 2026-02-13, 442 seconds after the EP/WXT trigger (J. Yang et al., GCN 43729). No optical source consistent with the EP/WXT (J. Yang et al., GCN 43729) was detected. We report the following results: start time t-t0(s) UL g' UL i' exposure_time (s) -------------------------------------------------------------- 20:05:43 467 16.3 17.1 50 20:07:04 694 19.6 20.1 300 20:18:05 1505 19.8 20.4 600 t is the middle time, t0 is the EP/WXT trigger time, t-t0 is given in seconds. UL gives the 5 sigma upper limit sensitivity in magnitudes, for images of the given exposure time. Calibration was done with 4 Pan-STARRS catalog stars on our images. No color or other corrections were applied to the values above. ---------------------------------- This research has been funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP26103591). The NUTTelA-TAO Team acknowledges the support of the staff of the Assy-Turgen Astrophysical Observatory, Almaty, Kazakhstan, and the Fesenkov Astrophysical Institute, Almaty, Kazakhstan. GRANDMA is a worldwide telescope network (grandma.ijclab.in2p3.fr) devoted to the observation of transients in the context of multi-messenger astrophysics (Antier et al. 2020 MNRAS 497, 5518). Kilonova-Catcher (KNC) is the citizen science program of GRANDMA (http://kilonovacatcher.in2p3.fr/). View this GCN Circular online at https://gcn.nasa.gov/circulars/43732. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...