TITLE: GCN CIRCULAR NUMBER: 12965 SUBJECT: GRB 120219A: MASTER-NET prompt and early optical observations DATE: 12/02/19 17:14:39 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs K.Ivanov, S.Yazev, N.M.Budnev, E.Konstantinov, V.Lenok, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University V.Krushinski, I.Zalozhnich, A. Popov Ural State University, Kourovka E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, P.V.Kortunov, A.Kuznetsov, M.Kornilov, A.Sankovich Sternberg Astronomical Institute, Moscow State University V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory H.Levato, C.Mallamaci, C.Saffe ICATE (Instituto de Ciencias Astronomicas, de la Tierra y del Espacio), San Juan, San Juan University, Felix Aguilar Observatory, Argentina MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Tunka was pointed to the GRB120219A (Swenson et al., GCN Circ 12964) 22 sec s after notice time and 105 sec after GRB time at 2012-02-19 14:31:54 UT. On our first (20s exposure, two "ra" and "dec" polarisation orientations) set we haven`t found optical transient within SWIFT XRT error-box. The 5-sigma upper limit in two polarizations has been about 17.3mag and 17.0 correspondingly. MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in Kourovka (Ural) was pointed to the GRB120219A (Swenson et al., GCN Circ 12964) 26 sec s after notice time and 109 sec after GRB time at 2012-02-19 14:31:58 UT. On our first (20s exposure, diagonal polarisation) set we haven`t found optical transient within SWIFT XRT error-box. The 5-sigma upper limit has been about 17.0 mag One MASTER Very Wide Field Camera located at Tunka (D=68 mm, 420 square degrees, 11 Mpx) was observed GRB error box with 5 s exposure befoure, during and after GRB Trigger Time without time gap between images. Our unfiltered images are calibrated relative to Tycho stars (V). The magnitude limit of the each emage is 11.5 m at the edge of FOW. We do not detect OT. But we need the duration and beginning time of the GRB. The redaction is continuated. The message may be cited.