Cosmic Rays and Dark Matter

Shoji Torii, currently Professor Emeritus and Distinguished Guest Research Professor at Waseda University, has dedicated his career to advancing our understanding of high-energy astrophysics and cosmic rays. After earning his PhD in Physics from Kyoto University in 1978, he built an impressive academic journey through positions at the University of Tokyo, Utah State University, and Kanagawa University before joining Waseda University in 2005. As Principal Investigator of the Calorimetric Electron Telescope (CALET) project since 2009, he has led an international collaboration between Japan, Italy, and the United States in developing and operating this sophisticated space telescope aboard the International Space Station. His groundbreaking work with CALET has yielded significant discoveries in cosmic ray electron spectrum measurements, extending up to 7.5 TeV, and has contributed to the search for dark matter signatures in space. His research achievements include numerous influential publications on cosmic ray observations, relativistic electron precipitation, and gravitational wave counterparts, earning him prestigious recognition including the ISAS Special Award in 2018. Under his leadership, CALET has become a crucial instrument in understanding high-energy phenomena in the universe, particle acceleration mechanisms, and the potential existence of dark matter, while also providing valuable data about the space radiation environment. His work spans from early balloon-based cosmic ray observations to leading the CALET Operations Center at Waseda University, where he continues to analyze data and push the boundaries of our understanding of the universe's most energetic phenomena.