GCN Circular 20922
Subject
GRB 170317A: POLAR observation
Date
2017-03-19T19:12:35Z (7 years ago)
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 2017-03-17 09:45:56.0 UT(T0), during a routine on-ground search of data, POLAR detected GRB 170317A
(Swift BAT (trigger # 742866); LaPorte et al., GCN 20885).
The POLAR light curve consists of one peak with duration (T90) of 6.00 � 1.00 s measured from T0.
The 1.00 s peak flux at T0 + 5.50 s is equal to 370 � 50 counts/sec.
POLAR recorded 1500 events from the burst.
Above measurements are in the energy range of about 15 - 300 keV.
LC_URL: http://polar.psi.ch/triggers/GRB_170317A.png
Using the best location from Swift-BAT, which is (J2000):
RA : 93.087 [deg]
Dec: 50.500 [deg]
the incident angle in the POLAR coordinate at T0 is:
Theta: 81.38 [deg]
Phi: 4.61 [deg]
The analysis results presented above are preliminary. 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.
