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GCN Circular 20274

GRB 161213A: POLAR Observation
2016-12-16T14:58:03Z (7 years ago)
Haulin Xiao at PSI/POLAR <>
R. Marcinkowski, H. Xiao and W. Hajdas in the name of POLAR Collaboration

At 2016-12-13T07:05:02 during a routine on-ground search of data, POLAR detected the GRB 161213A, which was also observed by the FERMI/GBM (trigger #503305506) and Integral/SPIACS (2016-12-13T07:05:02.85). The POLAR light curve consists of two main peaks with total duration of 7s. The 1s maximum peak flux is 370 +/- 50 cts/s (background subtracted). The total number of counts is 1360 +/- 140 (background subtracted). The above measurements are preliminary and estimated energy range is about 80 keV to 500 keV.

The incident angle in POLAR detector coordinate is:
theta:  46  [deg]
phi:    245 [deg]

This direction is computed using the best location from the FERMI/GBM, which is:
RA:   238 [deg]
Dec:   31 [deg]

The analysis results presented above are preliminary. The calibration work is ongoing. 
POLAR is a dedicated Gamma-Ray Burst polarimeter which was launched on-board the Chinese space laboratory Tiangong-2 (TG-2) on Sep 15, 2016.The energy detection range of POLAR is ~ 50-500 keV
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