Speaker
Description
Ultra-high-energy cosmic rays (UHECRs) are the most energetic charged particles observed in nature, but their sources and propagation processes are still not fully understood. The Telescope Array (TA) experiment, the largest UHECR observatory in the Northern Hemisphere, has achieved high-precision measurements of the cosmic ray energy spectrum through stable long-term operation and efficient data collection. These measurements reveal three prominent spectral features—the ankle, the shoulder, and the cutoff—which provide important insight into the origin and propagation of UHECRs. In this contribution, we present the latest energy spectrum measured with the TA surface detector array and discuss the observed differences between the UHECR energy spectra in the northern and southern skies.
