(Redirected from Carl D. Anderson)
Carl Anderson at
LBNL 1937
'Carl David Anderson' (
3 September 1905 –
11 January 1991) was a
U.S. experimental
physicist. He is best known for his discovery of the
positron, an achievement for which he received a
Nobel Prize in 1936.
Biography
Anderson was born in
New York City, the son of
Swedish immigrants. He studied physics and
engineering at
Caltech (
B.S.,
1927;
Ph.D.,
1930). Under the supervision of
Robert A. Millikan, he began investigations into
cosmic rays during the course of which he encountered unexpected
particle tracks in his
cloud chamber photographs that he correctly interpreted as having been created by a particle with the same mass as the
electron, but with opposite
electrical charge. This discovery, announced in
1932 and later confirmed by others, validated
Paul Dirac's theoretical prediction of the existence of the
positron. Anderson obtained the first direct proof that positrons existed by shooting
gamma rays produced by
thorium carbide (ThC
'') into other materials, resulting in creation of positron-electron pairs. For this work, Anderson shared the
Nobel Prize in Physics for
1936 with
Victor Hess.
[1]
Also in 1936, Anderson and his first graduate student,
Seth Neddermeyer, discovered the
muon (or 'mu-meson', as it was known for many years), a
subatomic particle 207 times more massive than the
electron. Anderson and Neddermeyer at first believed that they had seen the
pion, a particle which
Hideki Yukawa had postulated in his theory of the
strong interaction. When it became clear that what Anderson had seen was ''not'' the pion, theoretical physicist
I. I. Rabi, puzzled as to how the unexpected discovery could fit into any logical scheme of
particle physics, famously asked "Who ordered ''that''?" (sometimes the story goes that he was dining with colleagues at a Chinese restaurant at the time). The
muon was the first of a long list of
subatomic particles whose discovery initially baffled theoreticians who could not make the confusing 'zoo' fit into some tidy conceptual scheme.
Willis Lamb claimed that he had heard it said at one point that "the finder of a new elementary particle used to be rewarded by a Nobel Prize, but such a discovery now ought to be punished by a $10,000 fine."
Carl Anderson spent all of his career at
Caltech. During
World War II he conducted research in
rocketry. He died on
11 January,
1991, and is interred in the
Forest Lawn, Hollywood Hills Cemetery in
Los Angeles, California.
Selected papers
★ C.D. Anderson, "The Positive Electron", Phys. Rev. '43', 491 (1933)
Sources
★
American National Biography, vol. 1, pp. 445-446.
References
1. http://nobelprize.org/nobel_prizes/physics/laureates/1936/
External links
★
★
Annotated bibliography for Carl David Anderson from the Alsos Digital Library for Nuclear Issues
★