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GCN Circular 20272

GRB 161205A: POLAR observation
2016-12-16T12:30:18Z (7 years ago)
Zhao Yi at POLAR <>
Y. Zhao (IHEP), M. Z. Feng(IHEP), Z. H. Li (IHEP), Y. H. Wang (IHEP),
J. C. Sun (IHEP), H. C. Li (IHEP), S. L. Xiong (IHEP), T. Batsch(NCBJ),
T. Bernasconi (ISDC/UniGe), F. Cadoux (DPNC/UniGe), Y. W. Dong (IHEP),
M. Y. Ge (IHEP),W.Hajdas (PSI),Y. Huang (IHEP), Karol Jedrzejczak (NCBJ),
M. R. Kole (DPNC/UniGe), F. J. Lu (IHEP), R. Marcinkowski(PSI), 
M. Pohl (DPNC/UniGe), N. Produit (ISDC/UniGe),A. Rutczynska (NCBJ),
D. Rybka (NCBJ),L. M. Song (IHEP), J. Szabelski (NCBJ), X. Wen (IHEP),
 B. B. Wu (IHEP),X. Wu (DPNC/UniGe), H. L. Xiao (PSI), M. Xu (IHEP),
J. Zhang (IHEP),L. Y. Zhang (IHEP), P. Zhang (PSI), S. N. Zhang (IHEP),
Y. J. Zhang (IHEP), A. Zwolinska (NCBJ)
report for the POLAR collaboration:

At 2016-12-05T13:27:18UT(T0), during a routine 
on-ground search of data, POLAR detected the GRB 161205A, 
which was also observed by the Fermi/GBM (trigger502637242/161205561).

The POLAR light curve consists of multiple peaks
with a duration (T90) of 26.6s measured from T0-0.66s.
The 1s peak flux, measured from T0+7.00s, is 271.8cnts/s.
The total counts is about 1416cnts. The above measurements
are in the energy range of about 80-500 keV.


Using the best location from the Fermi/GBM, which is (J2000):
RA:   318.980 [deg]
Dec:  +47.650 [deg]
Err:  5.42    [deg]

the incident angle at T0 in POLAR detector coordinate is:
theta:  63.7 [deg]
phi:    -3.7 [deg]

The analysis results presented above are preliminary.

POLAR is a dedicated Gamma-Ray Burst polarimeter (50-500 keV) on-board 
the Chinese space laboratory Tiangong-2 launched on Sep 15, 2016. More
information about POLAR can be found at
, and
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