Swift GRB240123.46: Global MASTER-Net observations report

MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB240123.46 (trigger No 1210276,13h 17m 16.56s , +60d 37m 55.2s, R=0.05) errorbox 41 sec after notice time and 121 sec after trigger time at 2024-01-23 11:07:48 UT, with upper limit up to 17.6 mag. Observations started at twilight. The observations began at zenith distance = 68 deg. The sun altitude is -13.5 deg. The galactic latitude b = 56 deg., longitude l = 117 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2363206 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 131 | MASTER-Tunka | C | 20 | 17.6 | 160 | MASTER-Tunka | C | 20 | 17.6 | 186 | MASTER-Tunka | C | 15 | 17.5 | 209 | MASTER-Tunka | C | 15 | 17.5 | 229 | MASTER-Tunka | C | 10 | 17.4 | 247 | MASTER-Tunka | C | 10 | 17.3 | 265 | MASTER-Tunka | C | 10 | 17.4 | 284 | MASTER-Tunka | C | 10 | 17.1 | 302 | MASTER-Tunka | C | 10 | 17.4 | 320 | MASTER-Tunka | C | 10 | 17.5 | 339 | MASTER-Tunka | C | 10 | 17.4 | 357 | MASTER-Tunka | C | 10 | 17.3 | 375 | MASTER-Tunka | C | 10 | 17.5 | 394 | MASTER-Tunka | C | 10 | 17.4 | 412 | MASTER-Tunka | C | 10 | 17.2 | 430 | MASTER-Tunka | C | 10 | 17.4 | 448 | MASTER-Tunka | C | 10 | 17.3 | 466 | MASTER-Tunka | C | 10 | 17.4 | 486 | MASTER-Tunka | C | 10 | 17.4 | 504 | MASTER-Tunka | C | 10 | 17.4 | 522 | MASTER-Tunka | C | 10 | 17.4 | 541 | MASTER-Tunka | C | 10 | 17.4 | 559 | MASTER-Tunka | C | 10 | 17.4 | 577 | MASTER-Tunka | C | 10 | 17.4 | 595 | MASTER-Tunka | C | 10 | 17.4 | 613 | MASTER-Tunka | C | 10 | 17.4 | 632 | MASTER-Tunka | C | 10 | 17.4 | 651 | MASTER-Tunka | C | 10 | 17.4 | 669 | MASTER-Tunka | C | 10 | 17.4 | 706 | MASTER-Tunka | C | 10 | 17.4 | 724 | MASTER-Tunka | C | 10 | 17.4 | 743 | MASTER-Tunka | C | 10 | 17.4 | 761 | MASTER-Tunka | C | 10 | 17.5 | 781 | MASTER-Tunka | C | 10 | 17.4 | 799 | MASTER-Tunka | C | 10 | 17.5 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.