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GCN Circular 20719

GRB 170219A: POLAR Observation
2017-02-22T08:18:10Z (7 years ago)
Zhao Yi at POLAR <>
Minzi Feng (IHEP), Yi Zhao (IHEP), Yuanhao Wang (IHEP)
report on behalf of the POLAR collaboration:

At 2017-02-19T00:03:07.00 UT (T0), during a routine on-ground 
search of data, POLAR detected the GRB 170219A, 
which was also detected by the 
Fermi/GBM (trigger 509155392/170219002, Circ 20706),
CALET/GBM (Cherry et al. 2017, GCN 20710)
INTEGRAL/SPIACS (trigger 7701), Konus-Wind
(Frederiks et al. 2017, GCN 20703) and for which a triangulated
position was reported by IPN (Svinkin et al. 2017, GCN 20702).

The POLAR light curve consists of a single peak,
with a duration (T90) of 0.15 s measured from T0+0.08 s.
The 10-ms peak rate measured from T0+0.12 s is 16148.3 cnts/s.
The total counts is about 964 cnts. 


The above results are not dead time corrected. The above
measurements are in the energy range of about 20-500 keV.

Using the best location from the Fermi/GBM, which is (J2000):
RA:     72.730     [deg]
Dec:    +49.980    [deg]
Err:    2.88       [deg]

the incident angle in POLAR coordinate at T0 is:
theta:  59.8       [deg]
phi:    -90.2      [deg]

All 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 ,
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