TITLE: GCN CIRCULAR NUMBER: 27916 SUBJECT: Swift GRB200612.19: Global MASTER-Net observations report DATE: 20/06/12 05:07:18 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin, V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva, D.Kuvshinov, D. Cheryasov (Lomonosov Moscow State University, SAI, Physics Department), R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA), H.Levato (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE), R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias), D. Buckley (South African Astronomical Observatory), O.A. Gres, N.M. Budnev, O.Ershova (Irkutsk State University, API), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), V. Yurkov, A. Gabovich, Yu. Sergienko (Blagoveschensk Educational State University) MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) was pointed to the Swift GRB200612.19 (trigger No 977310,20h 10m 43.44s , -45d 21m 25.2s, R=0.05) errorbox 10 sec after notice time and 495 sec after trigger time at 2020-06-12 04:47:52 UT, with upper limit up to 18.3 mag. The observations began at zenith distance = 33 deg. The sun altitude is -81.6 deg. The galactic latitude b = -33 deg., longitude l = 355 deg. Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1380088 We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment _________|_____________________|_____|_______|______|________ 546 | MASTER-OAFA | C | 100 | 18.3 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.