******** NCTS/CTC/NTHU HEP Seminar ********

Speaker ： Prof. Hiroyuki Sagawa (ICRR)

Title ： Recent results on ultra-high-energy cosmic rays from the Telescope Array

Time ： 12:30-13:30, Thursday, 2023/10/12

Place ：R019, Physics Building, Nat'l Tsing Hua Univ.

Host ： Prof. Chong-Sun Chu (NTHU)

Abstract :
Cosmic rays with energies exceeding 10 to the 20th power electron volts have been
observed. However, their origin is still a mystery. The Telescope Array (TA)
experiment has been conducting observations to reveal the origin of ultra-high-
energy cosmic rays (UHECRs). The TA detector is located in the desert of Utah, USA
and is the largest UHECR observatory in the Northern Hemisphere. It consists of an
array of 507 surface particle detectors covering approximately 700 square
kilometers. Three fluorescence telescope stations were constructed around the
surface detector array. Here we present recent results on the energy spectrum, mass
composition, and anisotropy of arrival directions of UHECRs detected by the TA
experiment, including its two extensions: One is the TA Low Energy extension (TALE)
and the other is TAx4 which quadruples TA. Prospects for future UHECR observations
are also discussed.