Satellite-based Calibration of the TAIGA-HiSCORE Cerenkov Array by the LIDAR on-board CALIPSO

Discussion timeslot (ZOOM-Meeting): 16. July 2021 - 18:00
ZOOM-Meeting URL: https://icrc2021.desy.de/pf_access_abstracts
Corresponding Session: https://icrc2021-venue.desy.de/channel/Presenter-Forum-1-Evening-All-Categories/48
Abstract:
The wide-angle Air-Cerenkov array HiSCORE is a major component of the TAIGA facility in the Tunka valley, built for Gamma Astronomy and Cosmic Ray research. HiSCORE will contain 120 stations distributed over a 1km2 area.rnrnHere, we report a multi-year detection of light flashes in HiSCORE from the LIDAR on-board the Sun-synchronous CALIPSO satellite, obtained from 2015-2021. The 100mJ laser (532nm) is observed up to distances beyond 10km away from the ground light spot. This study complements first observations of a space-based LIDAR, performed in 2015/2017 with the 28-station HiSCORE prototype and the CATS LIDAR on-board the International Space Station. We present HiSCORE calibration methods developed for the LIDAR events to optimize the pointing resolution of the array, and additionally perform a detailed array performance analysis over 6 years.rnrnThe angular resolution for this special class of HiSCORE events - bright flashes, with a plane wave light front - is found to be smaller 0.05°, which is much below the high-energy limit of ~0.1° for air-showers. The satellite event sample allows to optimize rare event search strategies, like for optical flashes of astrophysical origin. We will also report on scheduled joint LIDAR observation by HiSCORE and TAIGA-IACTs, as well as optical ground instruments - to independently calibrate the absolute array-pointing precision.'

Authors: Andrea Porelli | Ralf Wischnewski | For the TAIGA Collaboration
Collaboration: TAIGA

Indico-ID: 1302
Proceeding URL: https://pos.sissa.it/395/876