Short GRB 170428A: MASTER-OAFA final reduction of the optical observations

MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in OAFA was pointed to the GRB170428A (Beardmore et al., GCN 21042) 17 sec after notice time and 31 sec after trigger time at 2017-04-28 09:14:14 UT (Podesta et al., GCN 21044). Our unfiletred limits are: Date time Exp Proc.type Lim. (s) 2017-04-28 09:14:14 10 Alert (SWIFT) 16.6 2017-04-28 09:15:04 20 Alert (SWIFT) 17.1 2017-04-28 09:16:07 30 Alert (SWIFT) 17.6 2017-04-28 09:17:19 40 Alert (SWIFT) 17.9 2017-04-28 09:18:42 60 Alert (SWIFT) 18.2 2017-04-28 09:20:24 80 Alert (SWIFT) 18.6 2017-04-28 09:17:19 180 SumAlert(SWIFT) 19.1 2017-04-28 09:22:28 110 Alert (SWIFT) 18.9 2017-04-28 09:24:59 140 Alert (SWIFT) 19.0 2017-04-28 09:28:01 170 Alert (SWIFT) 19.2 2017-04-28 09:22:28 420 SumAlert(SWIFT) 19.7 2017-04-28 09:31:33 180 Alert (SWIFT) 19.3 2017-04-28 09:35:16 180 Alert (SWIFT) 19.4 2017-04-28 09:38:59 180 Alert (SWIFT) 19.5 2017-04-28 09:31:33 540 SumAlert (SWIFT) 19.9 2017-04-28 09:42:42 180 Alert (SWIFT) 19.5 2017-04-28 09:48:50 180 Alert (SWIFT) 19.5 2017-04-28 09:55:02 180 Alert (SWIFT) 19.5 2017-04-28 09:42:42 540 SumAlert (SWIFT) 20.1 2017-04-28 09:58:46 180 Alert (SWIFT) 19.4 2017-04-28 10:02:26 180 Alert (SWIFT) 19.1 2017-04-28 10:06:07 180 Alert (SWIFT) 18.8 2017-04-28 09:58:46 540 SumAlert (SWIFT) 19.3 2017-04-28 10:09:49 180 Alert (SWIFT) 18.3 2017-04-28 09:31:33 1800 SumAlert (SWIFT) 20.3 2017-04-28 10:02:26 1440 SumAlert (SWIFT) 19.8 The message may be cited.