GCN Circular 20719
Subject
GRB 170219A: POLAR Observation
Date
2017-02-22T08:18:10Z (7 years ago)
From
Zhao Yi at POLAR <yizhao@ihep.ac.cn>
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.
LC_URL:
http://polar.ihep.ac.cn/grb/2017/02/GRB170219A/lc/POLAR_lc_grb170219A.png
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
http://polar.ihep.ac.cn/en/ , http://isdc.unige.ch/polar/
and http://polar.psi.ch/pub/.