{
  "bibcode": "2016GCN.20348....1M",
  "body": "Radoslaw Marcinkowski (PSI), Hualin Xiao (PSI) and Wojtek Hajdas (PSI) report on behalf of the POLAR collaboration:\n\nAt 2016-12-28T13:15:40.0 UT(T0), during a routine on-ground search of data, POLAR detected the GRB 161228B,\nwhich was also observed by Fermi GBM (trigger #504623745) and SPIACS (trigger: 2016-12-28T13-15-39.8537-31044-07056-0).\n\nThe POLAR light curve consists of one peak with duration (T90) of 8.5 +- 0.5 s measured from T0.\nThe  0.5 s peak flux at T0 + 3.25 s  is equal to 450 +- 40 cnts/sec.\nAbove measurements are in the energy range of about 80 - 500 keV.\n\nLC_URL: http://polar.psi.ch/triggers/GRB_161228B_raw.png\nand http://polar.psi.ch/pub/lc.php?event=GRB+161228B\n \n\nUsing the best location from the Fermi-GBM, which is (J2000):\n\nRA: 129.290  [deg]\n\t\nDec: 43.670  [deg]\n\nErr:  2.24   [deg]\n\nthe incident angle in the POLAR coordinate at T0 is:\n\nTheta: 28.7  [deg]\n\nPhi: 13.9  [deg]\n\nThe analysis results presented above are preliminary. Calibration of the instrument is ongoing.\n\nPOLAR is a dedicated Gamma-Ray Burst polarimeter which was launched on-board the Chinese space\nlaboratory Tiangong-2 (TG-2) on Sep 15, 2016. The energy detection range of POLAR is ~ 50-500 keV.\nMore information about POLAR can be found at http://polar.psi.ch/pub , http://polar.ihep.ac.cn/en/ and http://isdc.unige.ch/polar/ .\n\n\nThis message is quotable in publications.",
  "circularId": 20348,
  "createdOn": 1483098808000,
  "email": "hualin.xiao@psi.ch",
  "subject": "GRB 161228B: POLAR Observation",
  "submitter": "Haulin Xiao at PSI/POLAR  <hualin.xiao@psi.ch>",
  "eventId": "GRB 161228B"
}