TITLE: GCN CIRCULAR NUMBER: 6140 SUBJECT: GRB 070224: MASTER-Net refind analysis DATE: 07/02/24 22:53:17 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, E.Gorbovskoy, A.Krylov, N.Shatskiy, N.Tyurina,G.Borisov, A.Sankovich, V.Vladimirov, V.Vibornov, A.Kuznetsov Sternberg Astronomical Institute, Moscow Union 'Optic' A. Tlatov, I.Golubov Kislovodsk Solar Station of the Pulkovo observatory MASTER Very Wide Field Camera located at Kislovodsk Solar Station (http://observ.pereplet.ru, D=70 mm, 420 square degrees, 11 Mpixel's CCD) has moved to the Swift-BAT trigger 261880 and it has taken a series of 5s exposures starting 2 s after notice arrivel time at 20:29:38.285 UT under good weather condition and waxing moon. We note that the GBR position (J. L. Racusin et al. GCN Circ No. 6137) was at 4 degrees outside of the our field of view. We note that the VWF camera continuously takes frames during the night. These unfiltered images are calibrated relative to USNO A2.0 (R). The robot not find OT-candidate. T-Tgrb Mean Time Limit Coadd? Exp 100s 100.5s 11.0 no 5s 100s 130 s 12.0 yes 12x5s 100s 222 s 13.3 yes 47x5s MASTER robotic system (D=355mm, http://observ.pereplet.ru, Moscow) responded to GRB070224 (GRB_TIME is 2007-02-24 20:27:58.21). The first image was at 2007-02-24 20:30:04 UT, 51s after notice arrivel time and 00:02:05.79 after the GRB time at large zenit distance. The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B). The robot not find OT-candidate. T-Tgrb Mean Time Limit Coadd? Exp 125s 140s 16.2 no 30s 125s 924s 18.0 yes 31x30s This message can be cited. Mailto: lipunov@sai.msu.ru