{
  "bibcode": "2015GCN.17558....1G",
  "body": "E. Gorbovskoy, V. Lipunov, N.Tyurina, P.Balanutsa, A.Kuznetsov,\nD.Kuvshinov, V.Kornilov, \nLomonosov Moscow State University,\nSternberg Astronomical Institute\n\nA. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov\nKislovodsk Solar Station of the Pulkovo Observatory\n\nD.Buckley, S. Potter, A.Kniazev, M.Kotze\nSouth African Astronomical Observatory\n\nV.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov, A.Gabovich\nBlagoveschensk Educational State University, Blagoveschensk\n\nV.Krushinsky,\nUral Federal University, Yekaterinburg, Kourovka\n\nHugo Levato and Carlos Saffe\nInstituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)\n\nClaudio Mallamaci, Carlos Lopez and Federico Podest\nObservatorio Astronomico Felix Aguilar (OAFA)\n\n\nMASTER II  robotic telescope ( Lipunov et al., Advances in Astronomy, vol. \n2010, pp. 1-7, MASTER Global Robotic Net, 2010) \nlocated in Kislovodsk was pointed to the  GRB150309A 21 sec after notice \ntime and 96 sec after trigger time at 2015-03-09 23:04:45 UT in two \npolarizations. On our first (20s exposure)  set we not  found  optical \ntransient within SWIFT error-box (Cummings et al GCN 17553) brighter then \n17.2\n\nBefore this, the MASTER serial pointed to  FERMI (trig. N 447634793) \ncoordinates. Due to this pointings we have a two images from MASTER VWF \nvery wide fild camera  obtained at 2015-03-09 23:00:34 i.e. 152 sec before \nSWIFT BAT and  44 sec after FERMI GBM trigger times. We not found new OT \non this 5 sec exposure images with upper limit 12.0 at SWIFT position.\n\nTable 1. GRB 150309A MASTER optical upper limits.\n\nTstart  Tst-T0 Tmid-T0 Expt Mlimit  Instrum.   Coadd.\n23:00:34  -152    -149    5 12.0    MASTER VWF   no\n23:04:45    98     108   20 17.2    MASTER II    no\n23:04:45    98     559  780 19.3    MASTER II    10\n23:20:20  1033    2363 2160 20.0    MASTER II    12\n\nT0 - is a SWIFT trigger time.\n\nThe message may be cited.",
  "circularId": 17558,
  "createdOn": 1425988430000,
  "email": "lipunov@xray.sai.msu.ru",
  "subject": "GRB 150309A: MASTER prompt optical observation",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>",
  "eventId": "GRB 150309A"
}