{
  "bibcode": "2008GCN..8516....1G",
  "body": "E. Gorbovskoy, V. Lipunov, V.Kornilov, \nA.Belinski, N.Shatskiy, N.Tyurina, D.Kuvshinov, P.Balanutsa\nSternberg Astronomical Institute, Moscow State University\n\nA. Tlatov, A.Parkhomenko\nKislovodsk Solar Station of the Pulkovo Observatory\n\nV.Krushinski, I.Zalognikh\nUral State University, Kourovka\n\n\nS.Yazev, K.Ivanov\nIrkutsk State University\n\n\nTwo of the four  MASTER Very Wide Field Cameras located at Kislovodsk\n(http://apollo.sai.msu.ru/, D=50 mm, 4x1000 square degrees, 35'' per pix) has \nobserved the Swift-BAT GRB081102 error box  (Mangano et al., GCN Circ \n8470, Lipunov et al., GCN 8464, 8471) \nwith 5s exposures during all night without time gap between images. There \nare  two  separeted (~702m) mount with double cameras.\n\nNow we present results from the North and South mounts.\n\nThese unfiltered images are calibrated relative to Tycho stars (V).\nWe do not detect any new source at the XRT position\nreported in GCN Circ. 8470 (Mangano et al.) brighter than 13.0 \nmag before and after trigger time.\nThe photometry results +-4 min around trigger time:\n\n\n  T-T_trigger            m_lim (S/N=3)         Exposure         Coadd\n\n-255s... 0... 255 s       11.8                  5s              yes \n-2min...0...+2 min        12.7                 2x30s             12\n-2min...0...+2 min        13.0                 2x60s             24\n\nThe optical fluence during the 40s-GRBurst is limited by\n\n     <= 1.6x10_-8 erg/cm_2\n\n\nincluding 2.8 magnitude  absorbtion (Ukwatta et al., Circ 8462).\nThe  BAT-fluence is aboute 2.3x10_-6 erg/cm_2 (15-150 keV) \n(Fenimore et al., GCN 8468).\n\nSo:\n\nOptical Fluence/Gamma-Fluence(15-150keV) ~ < 1/140\n\nSame ratio for GRB080319B is ~ 1/25 (Naked Eye GRB) in 15-150 keV \n(Racusin, Karpov et al., Nature, vol.455, 183, 2008).\n\n\nScientific Master Team Report   are available at\nhttp://observ.pereplet.ru/images/GRB081102/grb_film.html\n\nNote: the GRB was at the edge of the FOW in both cameras.\nThe message may be cited.\n\nmailto: lipunov@sai.msu.ru",
  "circularId": 8516,
  "createdOn": 1226418610000,
  "email": "gcncirc@observ.inetcomm.ru",
  "subject": "GRB 081102: MASTER refind and final results",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs  <gcncirc@observ.inetcomm.ru>",
  "eventId": "GRB 081102"
}