Abstract
The Telescope Array (TA) experiment is a largest cosmic-ray observatory in the northern hemisphere, which aimed to study the origin of the ultrahigh energy cosmic rays (UHECRs). UHECRs with energies above \(10^{18}\) eV are expected to remember where they came from, despite deflections by galactic and extragalactic magnetic fields. TA consists of two types of detectors, an atmospheric fluorescence telescope and a surface detector array, enabling hybrid observations of air shower phenomena. The detector is located in the western desert of Utah, USA, at an altitude of 1400 m. The TA Low-energy Extension (TALE) experiment is located in the north of the site, which consits of also the fluorescence telescope and dense array, to observe the cosmic rays with energies above \(10^{16}\) eV. Furthermore, another extended experiment TA \(\times\) 4 which aimed to quadruple the detection area of TA is started. TA \(\times\) 4 started stable operation with fluorescence telescopes and the array of a half of planned area, and continue to expand the other half. We present the rescent results of TA/TALE/TA \(\times\) 4 experiment, including energy spectrum, anisotropy and mass composition in this report.
