Anderson , Carl David

Anderson , Carl David
(1905–1991) American physicist
Anderson, the son of Swedish immigrants, was born in New York City and educated at the California Institute of Technology where he obtained his PhD in 1930 and where he remained for his entire career, serving as professor of physics from 1939 until his retirement in 1978.
Anderson was deeply involved in the discovery of two new elementary particles. In 1930 he began to study cosmic rays by photographing their tracks in a cloud chamber and noted that particles of positive charge occurred as abundantly as those of negative charge. The negative particles were clearly electrons but those of positive charge could not be protons (the only positive particles known at the time) as they did not produce sufficient ionization in the chamber. Eventually Anderson concluded that such results “could logically be interpreted only in terms of particles of a positive charge and a mass of the same order of magnitude as that normally possessed by a free negative electron.” It was in fact the positron or positive electron, whose existence he announced in September 1932. In the following year his results were confirmed by Patrick Blackett and Giuseppe Occhialini and won for Anderson the 1936 Nobel Prize for physics.
In the same year Anderson noted some further unusual cosmic-ray tracks. As they appeared to be made by a particle more massive than an electron but lighter than a proton it was at first thought to be the particle predicted by Hideki Yukawa that was thought to carry the strong nuclear force and hold the nucleus together. The particle was initially named the ‘mesotron’ or ‘yukon’. However, this identification proved to be premature, as its interaction with nucleons was found to be so infrequent that it could not possibly perform the role described by Yukawa. From 1938 the particle became known as the meson, and the confusion was partly dispelled in 1947 when Cecil Powell discovered another and more active meson, to be known as the pi-meson or pion to distinguish it from Anderson's mu-meson or muon.

Scientists. . 2011.

Игры ⚽ Поможем решить контрольную работу

Look at other dictionaries:

  • Anderson,Carl David — Anderson, Carl David. 1905 1991. American physicist. He won a 1936 Nobel Prize for his discovery of the positron. * * * …   Universalium

  • Anderson, Carl David — ▪ American physicist born Sept. 3, 1905, New York, N.Y., U.S. died Jan. 11, 1991, San Marino, Calif.       American physicist who, with Victor Francis Hess (Hess, Victor Francis) of Austria, won the Nobel Prize for Physics in 1936 for his… …   Universalium

  • Carl David Anderson — 1937 Carl David …   Deutsch Wikipedia

  • Carl David Anderson — Saltar a navegación, búsqueda Carl David Anderson Carl David Anderson (n. Nueva York, 3 de septiembre de 1905 – † San Marino, California, 11 de enero de 1991). Físico …   Wikipedia Español

  • Carl David Anderson — Anderson en 1936 Naissance 3 septembre 1905 New York (USA) Décès 11 janvier 1991 …   Wikipédia en Français

  • Carl David Anderson — (n. Nueva York, 3 de septiembre de 1905 – † San Marino, California, 11 de enero de 1991). Físico estadounidense. Estudió en el Instituto Tecnológico de California, donde obtuvo el doctorado 1930. Posteriormente, en 1939, fue catedrático del… …   Enciclopedia Universal

  • Carl David Anderson — Infobox Scientist name = Carl David Anderson caption = Carl Anderson at LBNL 1937 birth date = birth date|1905|9|3 birth place = New York City, United States death date = death date and age|1991|1|11|1905|9|3 death place = San Marino, California …   Wikipedia

  • Carl David Anderson — noun United States physicist who discovered antimatter in the form of an antielectron that is called the positron (1905 1991) • Syn: ↑Anderson, ↑Carl Anderson • Instance Hypernyms: ↑nuclear physicist …   Useful english dictionary

  • Anderson's — Anderson , Carl David …   Scientists

  • Carl D. Anderson — Carl David Anderson Carl David Anderson au LBNL en 1937 Carl David Anderson (3 septembre 1905 à New York 11 janvier 1991 à Los Angeles) était un physicien américa …   Wikipédia en Français

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”