TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4549 SUBJECT: HETE Alert 4006: MASTER promt optical limit DATE: 06/01/20 21:03:06 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, A.Krylov, D.Kuvshinov, N.Tyurina, A.Belinski, E.Gorbovskoy, G.Antipov, V.Vladimirov, A.Sankovich, N.Shatsky Sternberg Astronomical Institute, Moscow Union 'Optic' Very Wide Field Camera of the MASTER robotic system (http://observ.pereplet.ru, 63.1x47.3 square degrees) imaged HETE fields-of-view before and after Probable GRB 060118 (TRIGGER_NUM:4006, GRB_TIME: 85556.51 SOD {23:45:56.51} UT). We analysed images (3 s exposition, unfiltred) before, during and after alert time. There is no OT brighter than 8m (unfiltred, under the very cold Moscow Moon night). JPG-images are available at: http://observ.pereplet.ru/images/GRB060118/before.jpg http://observ.pereplet.ru/images/GRB060118/after.jpg This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru