Latest results of ultra-high-energy cosmic ray measurements with prototypes of the Fluorescence detector Array of Single-pixel Telescopes (FAST)
astro-ph.IM
/ Authors
Toshihiro Fujii, Justin Albury, Jose Bellido, Ladislav Chytka, John Farmer, Petr Hamal, Pavel Horvath, Miroslav Hrabovsky, Hidetoshi Kubo, Jiri Kvita
and 21 more authors
Max Malacari, Dusan Mandat, Massimo Mastrodicasa, John Matthews, Stanislav Michal, Xiaochen Ni, Seiya Nozaki, Libor Nozka, Tomohiko Oka, Miroslav Palatka, Miroslav Pech, Paolo Privitera, Petr Schovanek, Francesco Salamida, Radomir Smida, Stan Thomas, Akimichi Taketa, Kenta Terauchi, Petr Travnicek, Martin Vacula, Seokhyun Yoo
/ Abstract
The origin and nature of ultra-high-energy cosmic rays (UHECRs) remain an open question in astroparticle physics. Motivated by the need for an unprecedented aperture for further advancements, the Fluorescence detector Array of Single-pixel Telescopes (FAST) is a prospective next-generation, ground-based UHECR observatory that aims to cover a huge area by deploying a large array of low-cost fluorescence detectors. The full-scale FAST prototype consists of four 20 cm photomultiplier tubes at the focus of a segmented mirror 1.6 m in diameter. Over the last five years, three prototypes have been installed at the Telescope Array Experiment in Utah, USA, and one prototype at the Pierre Auger Observatory in Mendoza, Argentina, commencing remote observation of UHECRs in both hemispheres. We report on the latest results of these FAST prototypes, including telescope calibrations, atmospheric monitoring, ongoing electronics upgrades, development of sophisticated reconstruction methods, and UHECR detections.