PEAK Staff Profile

Yasuyuki Matsuda, M.Sc., Ph.D (Kyoto University)
Associate Professor – Environmental Sciences

Contact : matsuday[at]


Matsuda Yasuyuki Prof. Matsuda earned his MSc and PhD in Science from Kyoto University for his research work on parity symmetry violation in nuclear reaction. The symmetries in nature have enchanted him since then, and Prof. Matsuda’s group currently engages in a research project which aims to measure antihydrogen atom’s ground-state hyperfine splitting. This measurement, being carried out at CERN, Switzerland, will test charge-parity-time symmetry (CPT symmetry) in unprecedented accuracy. The collaboration has attained an important milestone in 2010, generating an atomic beam of antihydrogen, which earned high credits including “the breakthroughs of the year” by from the Institute of Physics.

Research Interests

Prof. Matsuda’s group is also actively working on a research program to measure muonium atom’s ground-state hyperfine splitting. This experiment will utilize the high intensity muon beam available at J-PARC, Ibaraki-ken, Japan, and aims to measure the splitting to a precision of a few Hz, which is about 1/100000 of its natural width. Both experiments requires novel ways of detecting and processing small radiation signals in environment with large noise, and these techniques can be applied for radiation monitoring and remote sensing. All staff members at his laboratory speak English.

Selected Publications

“Synthesis of Cold Antihydrogen in a Cusp Trap”, Y. Enomoto et al.; Phys. Rev. Lett., 105, 243401(2010)
“Toward the first study of chemical reaction dynamics of Mu with vibrational state-selected reactants in the gas phase: the Mu + H₂*(v=1) reaction by stimulated Raman pumping”, P. Bakule et al.; Physica B Cond. Matt., 404, 1013-1016(2009)
“Search for strange tribaryon states in the inclusive ⁴He (K-stopped, p) reaction”, M. Sato et al.; Phys. Lett. B, 659, 107-102(2008)
“Pulsed source of ultra low energy positive muons for near-surface μSR studies”, P. Bakule et al.; Nucl. Instrum. Meth. B, 266, 335-346(2008)
“Precision measurement of the 3d→2p x-ray energy in kaonic ⁴He”, S. Okada et al.; Phys. Lett. B, 653, 387-391(2007)