{
  "bibcode": "2018GCN.23065....1L",
  "body": "V. Lipunov, E. Gorbovskoy, P.Balanutsa, N.Tiurina, D.Vlasenko, V.Kornilov, \nA.Kuznetsov,  V.Chazov, I.  Gorbunov, D.Zimnukhov, D.Kuvshinov, \nV.Vladimirov,\nLomonosov Moscow State University,SAI\n\nD.Svinkin (Ioffe Institute, StPetersburg, Russia)\n\nD. Buckley,\nSouth African Astronomical Observatory (SAAO)\n\nR. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres\nThe Instituto de Astrofisica de Canarias (IAC)\n\nA. Tlatov, V.Senik, D. Dormidontov\nKislovodsk Solar Station of the Pulkovo Observatory\n\nR. Podesta, F. Podesta, C. Lopez, C.Francile\nObservatorio Astronomico Felix Aguilar (OAFA)\n\nH.Levato,\nInstituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)\n\nO. Gres, N.M.Budnev , Yu.Ishmuhametova\nIrkutsk State University (ISU)\n\nA. Gabovich, V. Yurkov, Yu. Sergienko\nBlagoveschensk Educational State University (BSPU)\n\nMASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru) \nlocated in SAAO was starting survey on the IPN  GRB180728B error-box \n(Svinkin et al., GCN Circ #23056; Hamburg et al., GCN Circ #23057)  14269 \nsec after notice time and 70698 \nsec after trigger time at 2018-07-29 16:48:15 UT. The 5-sigma upper limit \non our first (180s exposure)  set is about 18mag.\n\nThe typical limit of coadded images is about 20 mag.\nWe marginally found one candidate to uncataloged object source near \nPGC052927 galaxy:\n\nMASTER OT J144922.8+164418.2\n\nRA,DEC = 14h 49m 22.8s +16d 44' 18.2\"    error = 0.7 arcsec\nmag = 19.7;\nThe offset from galaxy is 10.8W\tand 22.2N arcsec.\n\n====================================================================\n\nThe observations made on zenit distance = 50 degrees, galactic latitude b \n=  61 degree.\nThe moon (97 % bright part) below the horizon (The altitude of the Moon is \n-8 deg.\nObservations started at twilight.\nThe sun  altitude  is -11.1 deg.\nThe object can be observed till sunrise at 2018-07-30 05:26:48.\n\n\nThe covered map is available at\nhttp://master.sai.msu.ru/static//IPN/db/GRB180728.88/img/ligo_master_2018-07-30-16-09-11.eb.zoom.1.png\n\n\nWe reobserved possible transient on the next night starting 2018-07-30\n16:57:46 UT. We do not find the\nobject brighter than  20.5 .",
  "circularId": 23065,
  "createdOn": 1533020196000,
  "email": "lipunov@xray.sai.msu.ru",
  "subject": "GRB 180728B: MASTER optical observations short GRB IPN error box",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>",
  "eventId": "GRB 180728B"
}