Carl Anderson at LBNL 1937

Carl David Anderson (3 September 1905 – 11 January 1991) was a U.S. experimental physicist. He 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. Image File history File links Carl_anderson. ... Image File history File links Carl_anderson. ... The Berkeley Lab is perched on a hill overlooking the Berkeley central campus and San Francisco Bay. ... September 3 is the 246th day of the year (247th in leap years). ... 1905 (MCMV) was a common year starting on Sunday (see link for calendar). ... January 11 is the 11th day of the year in the Gregorian calendar. ... 1991 (MCMXCI) is a common year starting on Tuesday of the Gregorian calendar. ... ... Since antiquity, people have tried to understand the behavior of matter: why unsupported flowers drop to the ground, why different materials have different properties, and so forth. ... The construction of the Empire State Building, 1930. ... ... California Institute of Technology The California Institute of Technology (commonly known as Caltech) is a private, coeducational university located in Pasadena, California, in the United States. ... BS or bs is an abbreviation with multiple meanings, including: Bachelor of Science degree British Standard Bahamas (ISO country code) The postcode for Bristol, England A somewhat more polite abbreviation of bullshit A card game The Swiss canton of Basel_Stadt Shorthand for the backspace and the backspace control character Shorthand... 1927 (MCMXXVII) was a common year starting on Saturday (link will take you to calendar). ... Doctor of Philosophy, or Ph. ... 1930 (MCMXXX) is a common year starting on Wednesday. ... Robert Millikan. ... Cosmic rays can loosely be defined as energetic particles originating outside of the Earth. ... A subatomic particle is a particle smaller than an atom: it may be elementary or composite. ... The cloud chamber, also known as the Wilson chamber, is used for detecting particles of ionizing radiation. ... Properties The electron is a fundamental subatomic particle which carries a negative electric charge. ... Electric charge is a fundamental property of some subatomic particles, which determines their electromagnetic interactions. ... 1932 (MCMXXXII) is a leap year starting on Friday. ... Paul Adrien Maurice Dirac Paul Adrien Maurice Dirac, OM (August 8, 1902 – October 20, 1984) was a British theoretical physicist and a founder of the field of quantum physics. ... The first detection of the positron in 1932 by Carl D. Anderson The positron is the antiparticle or the antimatter counterpart of the electron. ... This article is about electromagnetic radiation. ... General Name, Symbol, Number thorium, Th, 90 Chemical series transition metals Group, Period, Block ?, 7, f Appearance silvery white Atomic mass 232. ... General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Atomic mass 12. ... This article does not cite its references or sources. ... Since antiquity, people have tried to understand the behavior of matter: why unsupported flowers drop to the ground, why different materials have different properties, and so forth. ... 1936 (MCMXXXVI) was a leap year starting on Wednesday (link will take you to calendar). ... Victor Francis Hess (June 24, 1883 – December 17, 1964) was an Austrian-American physicist. ...

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." 1936 (MCMXXXVI) was a leap year starting on Wednesday (link will take you to calendar). ... Seth Neddermeyer was a physicist who worked in the Manhattan project. ... The moons shadow, as seen in muons 700m below ground at the Soudan 2 detector. ... A subatomic particle is a particle smaller than an atom: it may be elementary or composite. ... Properties The electron is a fundamental subatomic particle which carries a negative electric charge. ... In particle physics, pion (short for the Greek pi meson = P middle) is the collective name for three subatomic particles discovered in 1947: π0, π+ and π−. Pions are the lightest mesons. ... Hideki Yukawa Hideki Yukawa (湯川 秀樹, January 23, 1907 - September 8, 1981) was a Japanese theoretical physicist and the first Japanese person to win the Nobel prize. ... The strong interaction or strong force is today understood to represent the interactions between quarks and gluons as detailed by the theory of quantum chromodynamics. ... Isidor Isaac Rabi (July 29, 1898 - January 11, 1988) was an American physicist of Austro-Hungarian origin. ... Particles erupt from the collision point of two relativistic (100GeV) gold ions in the STAR detector of the Relativistic Heavy Ion Collider. ... The moons shadow, as seen in muons 700m below ground at the Soudan 2 detector. ... Helium atom (not to scale) Showing two protons (red), two neutrons (green) and a probability cloud (gray) of two electrons (yellow). ... Willis Eugene Lamb, Junior (b. ...

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. California Institute of Technology The California Institute of Technology (commonly known as Caltech) is a private, coeducational university located in Pasadena, California, in the United States. ... Combatants Allied Powers Axis Powers Commanders {{{commander1}}} {{{commander2}}} Strength {{{strength1}}} {{{strength2}}} Casualties 17 million military deaths 7 million military deaths World War II, also known as the Second World War, was a mid-20th century conflict that engulfed much of the globe and is accepted as the largest and deadliest... A rocket is a vehicle, missile or aircraft which obtains thrust by the reaction to the ejection of fast moving exhaust from within a rocket engine. ... January 11 is the 11th day of the year in the Gregorian calendar. ... 1991 (MCMXCI) is a common year starting on Tuesday of the Gregorian calendar. ... Forest Lawn - Hollywood Hills Cemetery is located at 6300 Forest Lawn Drive in Los Angeles, California, on the south edge of the San Fernando Valley by Burbank (and on the north side of the Santa Monica Mountains from Hollywood). ... The City of Los Angeles (from Spanish; Los Ángeles) is the second-largest city in the United States in terms of population, as well as one of the worlds most important economic, cultural, and entertainment centers. ...

Selected papers

• C.D. Anderson, "The Positive Electron", Phys. Rev. 43, 491 (1933)