TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5026 SUBJECT: GRB060425:MASTER optical limit DATE: 06/04/28 16:19:06 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, N.Tyurina, A.Belinski, D.Kuvshinov, E.Gorbovskoy, A.Krylov, N.Shatskiy, G.Borisov, A.Sankovich, V.Vladimirov, P.Gritsyk, S.Korobkin Sternberg Astronomical Institute, Moscow Union 'Optic' MASTER robotic system (http://observ.pereplet.ru) observed GRB060425 error box (GRB_TIME is 2006-04-25 16:57:40 UT, IPN triangulation GCN5005) in survey mode at considerable zenit distances. The weather was good. We have two nights observations 2006-04-26 from 18:17:03.46 to 19:53:07.00 (1.05 - 1.12 days after the GRB time) (Lipunov et al.GCN5008) and 2006-04-27 from 18:57:50.89 to 19:21:19.88. We have 72 images. The location of our samples you can find at http://observ.pereplet.ru/images/GRB060425/GRB060425_ErrorBox_master.jpg The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). The robot not find OT brighter then 17.0 between 1.05 -1.12 day after GRB time in large IPN error box (J. Cummings, S. Barthelmy et al. GCN5005). The robot not find SN brighter then 17.5 in two nights. The search of the SN after several days is planed. MASTER team thanks to Konus-Wind team for collaboration. This work is supported by RFFI 04-02-16411 grant. This message can be cited. Mailto: lipunov@sai.msu.ru