{
  "bibcode": "2016GCN.19838....1R",
  "body": "R. Rebolo, M. Serra-Ricart, G. Israelian, N. Lodieu\nThe Instituto de Astrofisica de Canarias\n\nV. Lipunov, N.Tyurina, E. Gorbovskoy, V.Kornilov,\nP.Balanutsa, A.Kuznetsov, D.Kuvshinov\nLomonosov Moscow State University, Sternberg Astronomical Institute\n\nK.Ivanov, O.Gres, N.M.Budnev, S.Yazev,\nIrkutsk State University\n\nD.Buckley, S. Potter, A.Kniazev, M.Kotze\nSouth African Astronomical Observatory\n\nA. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko\nKislovodsk Solar Station of the Pulkovo Observatory\n\nV.Yurkov, Yu.Sergienko, A.Gabovich\nBlagoveschensk Educational State University, Blagoveschensk\n\nHugo Levato, Carlos Saffe\nInstituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)\n\nR.Podesta, C.Mallamaci, C.Lopez, F. Podesta\nObservatorio Astronomico Felix Aguilar (OAFA)\n\nMASTER-IAC  twin robotic telescope (MASTER-Net: \nhttp://observ.pereplet.ru, online view http://161.72.133.2/) \nlocated in IAC (Tenerife, Spain) was pointed to the \nGRB160821B (Siegel et al., GCN 19833) 34 sec after notice time \nand 53 sec after trigger time at 2016-08-21 22:30:06 UT.\n  The alert coordinates altitude was 55 deg. at MASTER-IAC, the Sun \naltitude was -35d, the Moon distance is 90 degrees.\n\nOn our first (10s exposure - two images in perpendicular polarizations)\nset  we  not found optical transient within SWIFT error-box (Evans et al., GCN 19837)\nand at NOT OT position  (Xu et al., GCN 19834) brighter then 16.6.\n\n\nThe resuts of the first 5 minutes observations are:\n\nId \tPro.type\tUT\tExp.time   Limit\tFilt.\t  Tube.\n                       (Start)     (s)     (5sigma)  (polarizator)\n\n285342   Alert       22:30:06     10       16.6           P-      WEST\n285343   Alert       22:30:06     10       16.6           P|      EAST\n285342   Alert       22:30:06     10       16.6           P-      WEST\n285345   Alert       22:30:43     20       17.1           P|      EAST\n285346   Alert       22:31:24     30       17.1           P-      WEST\n285347   Alert       22:31:24     30       16.6           P|      EAST\n285348   Alert       22:32:08     30       16.6           P-      WEST\n285349   Alert       22:32:08     30       16.6           P|      EAST\n285350   Alert       22:32:50     40       17.2           P-      WEST\n285351   Alert       22:32:50     40       17.0           P|      EAST\n285352   Alert       22:33:43     50       17.3           P-      WEST\n285353   Alert       22:33:43     50       17.2           P|      EAST\n285355\t Alert \t     22:34:46\t  70\t   17.5\t          P-\t  WEST\n285354\t Alert \t     22:34:46\t  70\t    0.0\t          P|\t  EAST\n\nThe limit of the coadded west tube images is 18.7 with start time \n22:30:06, finish time =  22:35:56 and mean time = 22:33:01 UT.\n\n\nThe message may be cited.",
  "circularId": 19838,
  "createdOn": 1471856922000,
  "email": "lipunov@xray.sai.msu.ru",
  "subject": "Short GRB 160821B: MASTER early  optical observations",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>",
  "eventId": "GRB 160821B"
}