The Telescope Array (TA) experiment has been observing extensive air showers (EAS) induced by ultrahigh energy cosmic rays (UHECR) since 2008. The TA$\times$4 upgrade aims to expand the detection area of TA at the highest energies to four times its original size with 500 additional surface detectors (SD) with the nearest neighbor spacing extended from 1.2km to 2.08km. Half of the new detectors...
The origin of ultra-high-energy cosmic rays (UHECRs) remains unsolved. Statistically identifying their sources requires long-term, all-sky observations that collect a sufficiently large event sample. To meet this challenge, we are developing CRAFFTโa low-cost atmospheric-fluorescence telescope that employs a Fresnel lens.
The current CRAFFT prototype has already recorded UHECR events with...
The Telescope Array (TA) experiment aims to elucidate the origin of ultra high energy cosmic rays. In this experiment, extensive air showers induced by ultra high energy cosmic rays are observed using Fluorescence Detector (FD) and Surface Detector (SD). The FD measures fluorescence light emitted by air showers and subsequently propagating through the atmosphere.
In the TA experiment,...
The Fluorescence detector Array of Single-pixel Telescopes (FAST) aims to increase the effective area for ultra-high-energy cosmic rays by deploying a large number of atmospheric fluorescence telescopes over a wide area for the next-generation experimental project like GCOS. The operation is expected to last for more than 10 years, and it is important to understand the aging of the equipment...
Fluorescence detector Array of Single-pixel Telescopes (FAST) is an R&D project focused on developing a low-cost fluorescence detector telescope. The FAST project currently operates three telescopes within the Telescope Array experiment, Utah, USA and two telescopes within the Pierre Auger Observatory, Argentina. The FAST telescopes are installed in a hut on a predefined location. The...
TALE infill experiment is further low-energy extension of Telescope Array Low-energy Extension (TALE), aiming to observe cosmic rays with energies from 1 PeV to 100 PeV, with the goal of revealing "knee" and "second knee" in the energy spectrum. 50 surface detectors (SDs) are deployed with 100 m spacing to observe this energy region.
The experiment began operation in November 2023 and has...
TA$\times$4 is an extension of the detection area for ultra-high-energy cosmic ray observations in the Telescope Array experiment. In the TA$\times$4 surface detector analysis, a lateral distribution function (LDF) is used to describe particle density as a function of distance from the air shower axis. The current TA$\times$4 analysis assumes a symmetric LDF around the shower axis; however,...
