Fermi GRB 241209D: 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) started inspect of the Fermi GRB 241209D ( Fermi GBM team, GCN 38488) errorbox 33914 sec after notice time and 33953 sec after trigger time at 2024-12-09 20:25:37 UT, with upper limit up to 19.2 mag. The observations began at zenith distance = 75 deg. The sun altitude is -41.5 deg. The galactic latitude b = 60 deg., longitude l = 302 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2701308 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 34044 | 2024-12-09 20:25:37 | MASTER-Tunka | (12h 40m 42.72s , -02d 49m 30.7s) | C | 180 | 15.0 | 34224 | 2024-12-09 20:25:37 | MASTER-Tunka | (12h 40m 42.76s , -02d 49m 32.4s) | C | 540 | 19.2 | Coadd 35267 | 2024-12-09 20:46:01 | MASTER-Tunka | (12h 40m 48.04s , -02d 50m 25.9s) | C | 180 | 18.8 | 36758 | 2024-12-09 21:10:52 | MASTER-Tunka | (12h 40m 47.42s , -02d 47m 55.6s) | C | 180 | 19.0 | 37967 | 2024-12-09 21:31:01 | MASTER-Tunka | (12h 40m 42.47s , -02d 48m 50.9s) | C | 180 | 19.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.