TITLE:   GCN CIRCULAR
NUMBER:  20469
SUBJECT: GRB 170114B: POLAR Observation
DATE:    17/01/16 09:45:23 GMT
FROM:    Haulin Xiao at PSI/POLAR  <hualin.xiao@psi.ch>

H.L. Xiao (PSI) , W. Hajdas (PSI) and R. Marcinkowski (PSI) report on behalf of the POLAR collaboration:
At 2017-01-14 19:59:12.0 UT(T0), during a routine on-ground search of data, POLAR detected GRB 170114B,
which was also observed by  Fermi GBM (trigger #506116757) and Konus-Wind at 71956.53s UT (19:59:16.53).


The POLAR light curve consists of one peak with duration (T90) of 12.0 +/- 1.0 s measured from T0.
Ten of 25 modules of POLAR recorded 5240 events from the burst.
The 1.0 s peak flux at T0 + 3.5 s  is equal to 750 +/- 60 counts/sec.
Above measurements are in the energy range of about 80 - 500 keV.

LC_URL: http://polar.psi.ch/triggers/GRB_170114B_10of25.png
     or raw LC: http://polar.psi.ch/pub/lc.php?event=GRB+170114B

Using the best location from Fermi GBM, which is (J2000):
RA : 137.9 [deg]
Dec: -28.5 [deg]
the incident angle in the POLAR coordinate at T0 is:
Theta: 102.0 [deg]
Phi: 140.6 [deg]

The analysis results presented above are preliminary. Calibration of the instrument 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.
More information about POLAR can be found at http://polar.psi.ch/pub ,
 http://polar.ihep.ac.cn/en/ and http://isdc.unige.ch/polar/ .

This message is quotable in publications.