Friday, July 11, 2008

Deceased--Yoji Totsuka

Yoji Totsuka
March 6th, 1942 to July 10th, 2008

"Japanese particle-physics leader dies"


Matin Durrani

July 11th, 2008

Yoji Totsuka, former director general of the KEK particle-physics lab in Japan, died yesterday at the age of 66. Totsuka, whose research interests were in the field of neutrino physics, served as KEK boss for three years from April 2003 After retiring in 2006, Totsuka became a professor emeritus at KEK and the University of Tokyo.

As KEK boss, Totsuka oversaw the Belle B-factory, in which collisions between electrons and positrons generate copious quantities of B-mesons, which are used to probe the differences between matter and antimatter. He was also in charge of the K2K neutrino-oscillation experiment, in which a beam of neutrinos is sent 250km to the vast underground SuperKamiokande detector at the Kamioka Observatory.

Before moving to KEK in October 2002, Totsuka was head of the SuperKamiokande experiment. Under Totsuka’s leadership, the experiment recorded the first ever evidence for neutrinos changing, or "oscillating", from one type to another, which indicated that these particles had mass. Until then, neutrinos were believed to be massless. Totsuka also oversaw the rebuilding of SuperKamiokande after most of its 11,000 photomultiplier tubes blew up in November 2001.

Born on 6 March 1942, Totsuka received his doctorate in 1972 from the University of Tokyo for research into cosmic-ray muons and then studied electron-positron collisions at the DESY lab in Hamburg, Germany. He joined the Kamiokande experiment — the forerunner of Superkamiokande — in 1981 and eventually became director of the Institute for Cosmic Ray Research at the University of Tokyo. The institute runs a range of astrophysics experiments, including the neutrino detectors at Kamioka.

During his lifetime, Totsuka received numerous awards including the Order of Culture of Japan and the Bruno Pontecorvo Prize in 2004. Current KEK boss Atsuto Suzuki paid tribute to Totsuka, calling him an "outstanding physicist" and "a prominent leader both in non-accelerator and accelerator neutrino experiments". Although Suzuki admitted that the pair had had "many discussions and sometimes quarrels", he praised Totsuka for being "very proactive in pushing foward international cooperation as members of many large particle laboratories".


He received his Bachelor of Science degree in 1965, his Master of Science degree in 1967 and his Doctor of Science degree in 1972 from the University of Tokyo.

He became a Research Associate of the University of Tokyo in 1972. After this position, Dr. Totsuka became an Associate Professor (1979-87), of the University of Tokyo, Professor of the University of Tokyo (1987-present), Director of the Kamioka Observatory, the Institute for Cosmic Ray Research (ICRR), the University of Tokyo (1995-present), Director of the Institute for Cosmic Ray Research (ICRR), the University of Tokyo (1997-present).

His main work has involved study of ultra-high-energy interactions in nuclear emulsions (1965-1966), study of muon bundles observed underground (1967-1972), study of e+e-collisions at DORIS, DESY (1972-1976), study of e+e-collisions at PETRA, DESY (1977-1980), search for proton decay and study of supernova-, solar- and atmospheric-neutrinos with Kamiokande-I, -II and -III (1981-1995) and study of astrophysical neutrinos and search for proton decay with Super-Kamiokande (1991-present).

Dr. Totsuka has received many notable awards, such as the Asahi Prize (1987), Nishina Prize (1988), Rossi Prize, American Astronomical Society, (1989), Inoue Prize (1990), EPS Special Prize, European Physical Society (1995).

He also belongs to the following society:
Japanese Physical Society
Japanese Astronomical Society
American Physical Society

No comments: