Masatoshi Koshiba
(Nobel Prize in Physics 2002, Distinguished University Professor)

Prof. Masatoshi Koshiba was born in Toyohashi city, Aichi Prefecture in 1926, and was brought up in Yokosuka City, Kanagawa Prefecture. After completing his education at Daiichi High School, he graduated from the department of physics, Faculty of Science, the University of Tokyo. He went on to the graduate school, but went to the U.S. to continue his studies at the University of Rochester where he set a record as the student who earned a doctoral degree in the shortest period of time.

After working as a research associate at the University of Chicago, he returned to Japan in 1958 to work as an Associate Professor at the Institute of Nuclear Study, the University of Tokyo. However, the University of Chicago wanted him back as the leader of the Japanese research group for an international joint experiment on cosmic rays. Then he was appointed as the leader of the whole experiment that used a balloon equipped with a nuclear emulsion. In 1962, he returned to Japan and in 1963 became an assistant professor of the Department of Physics, Faculty of Science. He started the experiment of cosmic ray μ particle flux in the Kamioka mine and from this time his relationship with the Kamioka mine started. About this time at a workshop in Moscow, he met Prof Gersh Itskovich Budker, who was then famous and was building an electron-positron collider (e⁺e^- collider) in Novosibirsk, Siberia, and they agreed to conduct a joint experiment with the collider. Soon after they had started preparing for the experiment, Prof. Budker fell sick and the research plan was held up. However, Prof. Koshiba visited several places in Europe and decided to join the DASP experiment at an e⁺e^- collider that was being built at DESY (German Electron Synchrotron). Shortly after the experiment started, a new particle called J/ψ was discovered both at the Brookhaven National Laboratory (USA) and at the Stanford Linear Accelerator Center (USA) almost at the same time in November 1974. As a result, the direction toward the current Standard Model of particle physics was fixed. The DASP experiment missed J/ψ, but the late Shuji Orito and other group members discovered related new particles. Thanks to these achievements, a bigger e⁺e^- collider, PETRA, was constructed at DESY, and Prof. Koshiba set up ICEPP (International Center for Elementary Particle Physics), which is attached to the Faculty of Science, to conduct international joint research with DESY. Through this research, the experimental groups discovered gluons that mediate strong interactions and later awarded the Special Prize from the European Physical Society.

In 1979, Prof. Koshiba started preparations for the Kamioka Nucleon Decay Experiment (Kamiokande) in Kamioka in order to discover nucleon decay predicted by the Grand Unified Theory. The experiment began operation in 1983. He could not find nucleon decay but on February 23, 1987, a month before his retirement from the University of Tokyo, he succeeded in detecting the neutrinos emitted from the supernova SN1987 explosion in the large Magellanic Cloud, which is located 170,000 light years away from the Earth. This happened because as Pasteur said, “Fortune favors those who prepare.” This finding led him to many honors and prizes: the Nishina Prize in 1987, the Asahi Prize in 1988, the Academy Award from the Academy of Japan in 1989, the Fujiwara Prize in 1997, and the Order of Cultural Merit in 1997.

Furthermore, Prof. Koshiba supported the late Professor Yoji Totsuka for the construction of Super Kamiokande, a bigger version of the Kamiokande, and built up a foundation for the discovery of neutrino oscillations. After that, he received more honors and prizes: the Wolf Prize in 2000, the Nobel Prize in physics in 2002, the Benjamin Franklin Medal in physics in 2003, the Grand Cordon of the Order of the Rising Sun in 2003, and the Erice Prize in 2007.

After retiring from the University of Tokyo, he worked as a professor at Tokai University from 1987 through 1996. In 2003, he established Heisei Foundation for Basic Science with the funds received from such awards as the Nobel Prize. Since then, he has been working as the chairman of the board of directors of the Foundation on development of basic science as well as enlightenment activities for young people. In 2005, he was chosen as a Distinguished University Professor by the University of Tokyo. Prof. Koshiba has nurtured a lot of researchers in the fields of particle accelerator and cosmic-ray experiments. With his sharp intuition, passion for research, and outstanding planning ability and leadership, he has established the foundations of the related fields of his research in Japan.

See also: http://nobelprize.org/nobel_prizes/physics/laureates/2002/

Profile

Current position

• Chairman, Board of Directors, Heisei Foundation for Basic Science
• Distinguished University Professor, the University of Tokyo

Date of birth

Academic history and professional highlights

March 1951	Bachelor in physics, Faculty of Science, the University of Tokyo
June 1955	PhD in physics, the University of Rochester
March 1958	Associate Professor, Institute of Nuclear Study, the University of Tokyo
November 1963	Associate Professor, Department of Physics, Faculty of Science, the University of Tokyo
June 1967	PhD in physics, the University of Tokyo
March 1970	Professor, Faculty of Science, the University of Tokyo
June 1974	Director of the Laboratory of High Energy Physics, Faculty of Science, the University of Tokyo
April 1977	Director of the LICEPP (Laboratory for International Collaboration for Elementary Particle Physics), Faculty of Science, the University of Tokyo
April 1984	Director of ICEPP (International Center for Elementary Particle Physics), Graduate School of Science, the University of Tokyo
March 31, 1987	Retirement
May 1987	Professor Emeritus, the University of Tokyo
August 1987 – March 1997	Professor, Tokai University
June 1994	Advising Councillor of ICEPP (International Center for Elementary Particle Physics), the University of Tokyo
December 2002	Member of the Japan Academy
October 1, 2003	Founder, Chairman of Board of Directors, Heisei Foundation for Basic Science
January 2005 – Present	Distinguished University Professor (the University of Tokyo)

Honors & Awards

1985	Der Grosse Verdienstkreutz from the President of Federal Republic of Germany
1987	The Nishina Prize from the Nishina Foundation
1988	The ASAHI Prize from the ASAHI Press
1988	Person of Cultural Merit by the Japanese Government
1989	The Academy Award from the Academy of Japan
1997	The Fujiwara Prize from the Fujiwara Science Foundation
1997	The Order of Cultural Merit conferred by The Emperor of Japan in person
2000	The Wolf Prize from The State President of Israel
2002	Nobel Prize in Physics
2003	Benjamin Franklin Medal in Physics
2003	The Grand Cordon of the Order of the Rising Sun
2007	Ettore Majorana - Erice - Science for the Peace from the World Federation of the Scientists