[vsnet-grb-info 19155] GRB 170220A: POLAR Observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20733
SUBJECT: GRB 170220A: POLAR Observation
DATE:    17/02/24 14:50:14 GMT
FROM:    Haulin Xiao at PSI/POLAR  <hualin.xiao at psi.ch>

R. Marcinkowski (PSI), H.L. Xiao (PSI) and W. Hajdas (PSI) report on behalf of the POLAR collaboration:

At 2017-02-20 18:48:01.00 UT(T0), during a routine on-ground search of data, 
POLAR detected short GRB 170220A, which was also observed by Konus at 18:47:58.467 UT.
 

The POLAR light curve consists of 1 peak with duration (T90) of 0.3 +/- 0.1 s measured from T0. 
The 50 ms peak flux at T0 + 0.7 s is equal to 7300 +/- 100 counts/sec. 
POLAR recorded 1230 events from the burst. 
Above measurements are in the energy range of about 50 - 500 keV.
 
LC_URL: http://polar.psi.ch/triggers/GRB_170220A_raw.png
     or http://polar.psi.ch/pub/lc.php?event=GRB+170220A

 
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.