Prizes & Awards

Prof. Ryugo Hayano Wins the 2008 Nishina Memorial Prize

  • K. Ozawa (Lecturer, Department of Physics)
Figure 1

Prof. Ryugo Hayano

The Nishina Memorial Prize is a historic prize that was established to commemorate the late Dr. Yoshio Nishina's achievements. It aims to honor scientists who have made an outstanding contribution to researches closely related to Nuclear Physics. Previous winners of the Prize from the School of Science, the University of Tokyo are: Dr. Msatoshi Koshiba (Honorary Professor Emeritus), Akito Arima (former President of the University) and Toshimitsu Yamazaki (Professor Emeritus).

Prof. Ryugo Hayano has opened up new physics by creating extraordinary atoms such as pionic atoms and antiprotonic atoms that do not exist in nature and carrying out their precise measurement. Above all things, his research on antiprotonic helium atoms is attracting global attention as an experiment that can verify the symmetry between matter and antimatter (CPT symmetry) with high-precision.

Antiprotonic helium atoms were discovered by Prof. Hayano at KEK and their laser spectroscopy was established at CERN in 1993 by him. In addition, since the year 2000 at CERN's antiproton decelerator facility, the ASACUSA collaborators led by Prof. Hayano have developed and introduced cutting-edge equipments one after another (e.g. high-precision pulsed laser) and succeeded in measuring the mass ratio of antiprotons and electrons at the relative accuracy of 10-9.

In the latest edition of “Fundamental Physical Constant” published by CODATA (Committee on Data for Science and Technology), it is specified that this result has contributed to the determination of Rydberg Constant and proton-electron mass ratio, which is a rare example of Japanese research achievements' involvement in the measurement of Fundamental Physical Constant.

Title of the Prize: For the study of antiprotonic helium atoms