GCN Circular 39419
Subject
GRB 250219A: NUTTelA-TAO / BSTI Optical Limits
Date
2025-02-22T07:47:55Z (15 days ago)
From
Toktarkhan Komesh at Nazarbayev University <toktarkhan.komesh@nu.edu.kz>
Via
Web form
T. Komesh (NU), Z. Abdullayev (NU), Z. Maksut (NU), D. Berdikhan (NU), B. Grossan (UCB, NU), M. Krugov (FAI) and E. Abdikamalov (NU) report on behalf of the Energetic Cosmos Laboratory:
We imaged the field of GRB 250219A with the Nazarbayev University Transient Telescope at Assy-Turgen Astrophysical Observatory (NUTTelA-TAO) starting at 21:54:17 UT on 2025-02-19, 6.0 hours after the SVOM/ECLAIRs trigger (F. Daigne et al., GCN 39376). Observations were made in clear conditions. No source consistent with the XRT (J. A. Kennea et al., GCN 39379) was detected. We report the following results:
start time t-t0 (minute) end time UL g' UL r' exposure_time (s)
------------ --------------------------------------------------
21:54:17 361 21:55:17 19.29 19.09 60
21:58:38 365 22:02:38 19.57 19.49 240
t is the middle time, t0 is the SVOM/ECLAIRs trigger time, t-t0 is given in minutes. 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.
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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. 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, Kazkhstan.