The time calibration system for the LHAASO-WCDA experiment
August 16, 2017
August 03, 2018
The Water Cherenkov Detector Array (WCDA), which is one of the main components of the Large High Altitude Air Shower Observatory
(LHAASO), functions as surveying the northern sky for high-energy gamma ray sources at the energy range around 100 GeV–30 TeV. The
precision of the time measurement for shower particles hitting every detector in the array directly associates the detection sensitivity for the sources. In order to make the pointing error of the detector to any point source less than 0.1 ◦ , the calibration precision of the time offsets among detector cells should be less than 0.2 ns. To reach this goal, a method called “cross calibration” is to be employed for the detector array, with 180 bundles of fiber systems guiding the lights of LEDs to each PMT. A prototype of the time calibration system is developed, which is based on a fast LED, a plastic fiber bundle and an FPGA control board. The prototype is tested in the lab and the error propagation based on the measured parameters shows that it fulfills the requirement.
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating
very compact bibliographies which can be beneficial to authors and
readers, and in "proceeding" format
which is more detailed and complete.