Toshiko Yuasa was an internationally active woman physicist who was based in France.
Yuasa was born in 1909 in Tokyo. She attended the Division of Science, Tokyo Women’s Higher Normal School, and moved on to the Department of Physics, Tokyo Bunrika University. In 1934 she graduated from the university and began physics research. Gender discrimination was still strong, however, and it was difficult to find a position where she could conduct the research she wanted. It was around this time that the Joliot-Curies discovered artificial radioactivity, and Yuasa, deeply moved by their paper, decided to travel to France.
When Yuasa arrived in March 1940, Paris was under martial law, and in June was overtaken by Germany. Yuasa survived these difficulties by devoting herself to research. Under Professor Joliot-Curie (Madame Curie’s son-in-law) at the Nuclear Chemistry Laboratory of Collége de France, Yuasa used a Wilson chamber to analyze the tracks of alpha and beta rays generated by artificial radioactive nuclei, and began research to discover the mechanism of decay and energy structure. Her research that covered analysis of the energy spectrum of beta rays and the form of interaction that causes decay was highly acclaimed, and her paper, "Contribution à l'étude du spectre continu des rayons β- émis par les corps radioactifs artificiels (Continuous beta-ray spectrum generated by artificial radioactivity)" earned her a French doctorate degree in science in 1943.
In the summer of 1944, just before Paris was freed by the Allied forces, she was forced to transfer to Berlin. She temporarily lost freedom to conduct research, but then created a beta-ray spectrometer throughout the air raids and returned to Japan just before the war ended with the fall of Berlin, bringing her instruments with her. Yuasa returned to Tokyo Women’s Higher Normal School as a professor, but was prevented from continuing research due to the US occupation forces’ ban on nuclear research. Three and a half years later, in 1949, she returned to France on Professor Joliot’s invitation and this time stayed. She went on to establish a solid position as a researcher at the French National Center for Scientific Research.
Around 1960 she transferred to the field of nuclear reaction, which uses synchrocyclotrons. From around 1967 she began to work on Japanese-French exchange, inviting young researchers from Japan, while also taking on innovative issues herself. She achieved results that attracted global attention. She proposed a Japan-France joint project for research on few-nucleon systems, and made every effort to realize this even through illness and death.
Yuasa is also known for her contributions to cultural exchange, by introducing French culture to Japan and taking care of Japanese visitors to France. She earnestly considered issues such as "women and science" and "peace." Many people have been moved by her collection of reflections on science and life, scholarship and art, and science and religion in the three-part book series, Pari zuiso (Paris essays), as well as other books and contributions. Ochanomizu University currently offers the "Toshiko Yuasa Memorial Scholarship Fund for Special Researchers," in memory of her contributions to nuclear physics research and French-Japanese relations, and to encourage the international activities of young scientists today.
略歴
1909 | December 11, born in Shitaya Ward (current Taito Ward), Tokyo |
1927 | Enters the Division of Science, Tokyo Women’s Higher Normal School |
1931 | Graduates from the Division of Science, Tokyo Women’s Higher Normal School (Photo), enters the Department of Physics, Tokyo Bunrika University (age 21) |
1934 | Graduates from the Department of Physics, Tokyo Bunrika University, becomes an assistant at the same. Begins research on nuclear spectroscopy |
1935 | Becomes a teacher at Tokyo Woman’s Christian University (until 1937) |
1938 | Becomes an assistant professor at Tokyo Women’s Higher Normal School |
1940 | Travels to France (age 30). Begins nuclear research under Professor F. Joliot-Curie at the Nuclear Chemistry Laboratory of Collége de France. |
1943 | [December] Receives a doctorate in science from France (age 33); doctoral thesis, "Contribution à l'étude du spectre continu des rayons β- émis par les corps radioactifs artificiels (Continuous beta-ray spectrum generated by artificial radioactivity)" |
1944 | [August] Transfers to Berlin due to the Allied forces’ advance on Paris. Begins research at the First Physics Laboratory of the University of Berlin |
1945 | [April] Creates double-focusing spectrometer for beta-ray spectrum. [May] Returns to Japan via Siberia.[October] Becomes a professor at Tokyo Women’s Higher Normal School (age 35) |
1946 | Commissioned by Riken Nishina Center (until 1949) |
1948 | Also takes on position as lecturer at the Institute for Chemical Research, Kyoto University (until 1949) |
1949 | [February] Returns to France. Begins research on nuclear spectroscopy as a researcher at the French National Center for Scientific Research (CNRS) |
1952 | Becomes a professor at Ochanomizu University. Takes leave of absence from the same |
1955 | [September] Retires from Ochanomizu University |
1957 | Becomes a senior researcher at CNRS (age 47) |
1962 | Receives doctorate in science from Kyoto University; doctoral thesis, "Étude du type d’invariant de l’interaction Gamow-Teller en désintégration β- de 6He (Form of Gamow-Teller invariant interaction on beta decay of 6He)." Begins research on medium energy nuclear reaction |
1967 | [August-October] Returns to Japan for the International Nuclear Physics Conference (Tokyo) |
1973 | [May] Has stomach and gall-bladder partially removed (age 63) |
1974 | [December] Retires from CNRS, but continues with research |
1975 | Becomes emeritus researcher at CNRS (age 65) |
1976 | Receives a Medal with Purple Ribbon (age 66) |
1977 | [August-October] Returns to Japan for the International Nuclear Physics Conference (Tokyo) |
1978 | Submits proposal on Japan-France joint-research on few-nucleon systems |
1980 | [Late January] Is hospitalized at Centre Henri Becquerel, located in the suburbs of Paris. February 1, passes away at the age of 70. Receives the Order of the Precious Crown of the Third Class |
Materials
- "Sketches"
- "Photographs"