MAXI GRB210528.95: Global MASTER-Net observations report

MASTER-IAC robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Spain (IAC Teide Observatory) started inspect of the MAXI GRB210528.95 (trigger No 362758075,15h 58m 09.36s , +05d 58m 58.8s, R=1) errorbox 10 sec after notice time and 4707 sec after trigger time at 2021-05-29 00:10:22 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 23 deg. The sun altitude is -39.0 deg. The galactic latitude b = 40 deg., longitude l = 16 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1623577 We obtain a following upper limits. Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment _________|_____________________|_____________________|____________________________________|_____|_______|_______|________ 4798 | 2021-05-29 00:10:22 | MASTER-IAC | (15h 57m 01.56s , +06d 02m 14.3s) | P| | 180 | 18.5 | 4798 | 2021-05-29 00:10:22 | MASTER-IAC | (15h 56m 10.28s , +06d 08m 43.9s) | P- | 180 | 18.3 | 4998 | 2021-05-29 00:13:42 | MASTER-IAC | (15h 57m 09.19s , +06d 02m 16.4s) | P| | 180 | 18.7 | 4998 | 2021-05-29 00:13:42 | MASTER-IAC | (15h 56m 17.67s , +06d 08m 46.0s) | P- | 180 | 18.3 | 5198 | 2021-05-29 00:17:02 | MASTER-IAC | (15h 57m 06.12s , +06d 03m 54.3s) | P| | 180 | 18.7 | 5198 | 2021-05-29 00:17:02 | MASTER-IAC | (15h 56m 14.54s , +06d 10m 23.3s) | P- | 180 | 18.4 | 5398 | 2021-05-29 00:20:22 | MASTER-IAC | (15h 57m 06.18s , +06d 02m 37.0s) | P| | 180 | 18.8 | 5398 | 2021-05-29 00:20:22 | MASTER-IAC | (15h 56m 14.59s , +06d 09m 05.6s) | P- | 180 | 18.4 | The observation and reduction will continue. The message may be cited.