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Cesare Mansueto Giulio Lattes (born 11 July 1924, Curitiba, Paraná, Brazil, died 8 March 2005, Campinas, São Paulo), also known as Cesar (or César) Lattes, was a Brazilian experimental physicist, one of the discoverers of the pion, a composite subatomic particle made of a quark and an antiquark. ==Life== Lattes was born to a family of Italian-Jewish immigrants in Curitiba, Brazil. He did his first studies there and also in São Paulo. He then went to the University of São Paulo, graduating in 1943, in mathematics and physics. He was part of an initial group of young Brazilian physicists who worked under European teachers such as Gleb Wataghin and Giuseppe Occhialini. Lattes was considered the most brilliant of those and was noted at a very young age as a bold researcher. His colleagues, who also became important Brazilian scientists, were Oscar Sala, Mário Schenberg, Roberto Salmeron, Marcelo Damy de Souza Santos and Jayme Tiomno. At the age of 25, he was one of the founders of the Brazilian Center for Physical Research (''Centro Brasileiro de Pesquisas Físicas'') in Rio de Janeiro. From 1947 to 1948, Lattes launched on his main research line by studying cosmic rays. He visited a weather station on top of the 5,200-meter high Chacaltaya mountain in Bolivia, using photographic plates to register the rays. Travelling to England with his teacher Occhialini, Lattes went to work at the H. H. Wills Laboratory of the University of Bristol, directed by Cecil Powell. There, he improved on the nuclear emulsion used by Powell by adding more boron to it. In 1947, he made his great experimental discovery with Powell: the pion (or pi meson). Lattes then proceeded to write a paper for ''Nature'' without bothering to ask for Powell's consent. In the same year, he was responsible for calculating the new particle's mass. A year later, working with Eugene Gardner at UC Berkeley, Lattes was able to detect the artificial production of pions in the lab's cyclotron, by bombarding carbon atoms with alpha particles. He was just 24 years old. In 1949, Lattes returned as a professor and researcher with the Federal University of Rio de Janeiro and the Brazilian Center for Physical Research. After another brief stay in the United States (from 1955 to 1957), he returned to Brazil and accepted a position at his ''alma mater'', the Department of Physics of the University of São Paulo. In 1967, Lattes accepted a position of full professor with the new "Gleb Wataghin" Institute of Physics at the State University of Campinas (Unicamp), which he helped to found. He became also the chairman of the Department of Cosmic Rays, Chronology, High Energies and Leptons. In 1969, he and his group discovered the mass of the so-called fireballs, a phenomenon induced by naturally occurring high-energy collisions, and which was detected by means of special lead-chamber nuclear emulsion plates invented by him, and placed at the Chacaltaya peak of the Bolivian Andes. Lattes retired in 1986, when he received from the Unicamp the titles of doctor ''honoris causa'' and professor emeritus. After retirement he continued to live in a house in the suburban area very near to the University's campus. He died of a heart attack on March 8, 2005. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「César Lattes」の詳細全文を読む スポンサード リンク
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