|Research Fields||Astrophysics, Astroparticle physics|
|Academic Society Membership||The Physical Society of Japan; The Astronomical Society of Japan|
Our Universe is filled with high-energy charged particle called cosmic rays. The velocity of high-energy cosmic rays reaches 99.9999999999% of the speed of light. The origin and production mechanism of these particles are still unknown. Since cosmic rays are deflected by cosmic magnetic fields, it is difficult to identify their origin by direct observations. Cosmic rays produce neutrinos, neutral subatomic particles, via interaction with ambient particles. Since neutrinos arrive on Earth straightly from the sources, we can identify cosmic-ray sources by neutrino signals. Since this method uses neutrino signals in addition to electromagnetic signals used in traditional astronomy, we call it “multi-messenger astrophysics”.
I am theoretically predicting neutrino signals as well as electromagnetic signals from cosmic-ray source candidates, and compare the theoretical predictions with current observational data to constrain theoretical models. Also, I am performing numerical simulations of cosmic-ray production in extreme environments of astrophysical plasmas, such as the vicinity of black holes. Combining the plasma simulations and predictions of neutrino and electromagnetic signals, together with rich observational data obtained by near-future facilities, I would like to reveal the origin and production mechanism of mysterious high-energy particles from the Universe.