{
  "bibcode": "2018GCN.22444....1V",
  "body": "V.Vladimirov, V. Lipunov, E.Gorbovskoy, N.Tyurina, V.Kornilov, \nD.Zimnukhov,   A.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.Chazov, \nD. Kuvshinov (Lomonosov Moscow State University, SAI)\n\nA. Tlatov, V.Senik, D. Dormidontov\n(Kislovodsk Solar Station of the Pulkovo Observatory)\n\nD.Buckley, S. Potter\n(South African Astronomical Observatory),\n\nO.Gres,  N.M.Budnev\n(Irkutsk State University),\n\nV.Yurkov, A.Gabovich, Yu.Sergienko\n(Blagoveschensk Educational State University, Blagoveschensk),\n\nR.Podesta, C.Lopez, F. Podesta\n(Observatorio Astronomico Felix Aguilar (OAFA),\nNational University of San Juan,  Argentina),\n\nH. Levato, C. Saffe\n(Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), \nSan\nJuan, Argentina),\n\nR. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres\n(The Instituto de Astrofisica de Canarias),\n\n\n\nMASTER-Kislovodsk (Russia)  robotic telescope (MASTER-Net: \nhttp://observ.pereplet.ru) located in Kislovodsk was pointed to\nthe  GRB180224.93 21 sec after  notice time and 37 sec after trigger time \nat 2018-02-24 22:21:44 UT. On our  unfiltered polarizing  exposures\nset we  found 1 bright optical transient within  SWIFT\nerror-box (ra=202.658 dec=38.0878 r=0.05) \nbrighter then 18.1.\n\nRA,DEC  = 13h 30m 44.057s , +38d  04m 44.55 s\nError = 0.1 arcsec\nmaximal magnitute ~ 16.7\n\n\nThe 5-sigma upper limit has been about 18.1mag\nThe message may be cited.\n\n\n====================================================================\n\n\n\nThe observations made on zenit distance = 23 degrees, galaxy latitude b = \n76 degree.\nThe moon (68 % bright part) is 16 degrees above the horizon. The distance \nbetween  moon and  object is 97 degrees.\nThe sun  altitude  is -53.0 degree.\nThe object can be observed till sunrise at 2018-02-25 03:53:29 UT.\n\n\nMASTER-SAAO  robotic telescope (MASTER-Net: http://observ.pereplet.ru) \nlocated in SAAO was pointed to the  GRB180224.94 92 sec after notice time \nand 176 sec after trigger time at 2018-02-24 22:24:12 UT. On our first\n  set we  not found optical transient within SWIFT error-box \n(ra=202.638 dec=38.0819 r=0.1) brighter then 15.8.\n\nThe 5-sigma upper limit has been about 15.8 mag\nThe message may be cited.\n\n\nThe observations made on high zenit distance = 82 degrees, galaxy latitude \nb = 76 degree.\nThe moon (68 % bright part) is  6 degrees above the horizon. The distance \nbetween  moon and  object is 97\nThe sun  altitude  is -48.3 degree.\nThe object can be observed till sunrise at 2018-02-25 04:21:26.\n\n\nThis message can be cited.",
  "circularId": 22444,
  "createdOn": 1519554801000,
  "email": "lipunov@xray.sai.msu.ru",
  "subject": "GRB180224A: Global MASTER-Net bright OT detection",
  "submitter": "Vladimir Lipunov at Moscow State U/Krylov Obs  <lipunov@xray.sai.msu.ru>",
  "eventId": "GRB 180224A"
}