James Cronin, CP Violation and the Pierre Auger Observatory

Resources with Additional Information

James Cronin
Courtesy Brookhaven
National Laboratory

James Watson Cronin "received his B.S. degree from Southern Methodist University in 1951. He then attended the University of Chicago for graduate school, earning his M.S. in 1953 and his Ph.D. in 1955.

He began his scientific career at Brookhaven National Laboratory, where he served as an assistant physicist from 1955 to 1958. Cronin joined the faculty at Princeton University in 1958, where he remained until 1971, when he was appointed the University Professor of Physics at the University of Chicago. He became University Professor Emeritus of physics in 1997."1

"While working at Brookhaven National Laboratory in 1964, Cronin and [Val L.] Fitch, both then at Princeton, observed the first example of nature’s preference for matter over antimatter."1 "The experiment uncovered the CP [charge-parity] violation, or a break in particle-antiparticle symmetry, and earned Cronin and Fitch the 1980 Nobel Prize in Physics ."2

"Later in his career, Cronin and a colleague initiated the Pierre Auger Project, a $50 million collaboration of more than 250 scientists in 17 nations to track down the mysterious sources of rare but extremely powerful cosmic rays that periodically bombard Earth. "1 "Cronin … is spokesman emeritus for Argentina’s Pierre Auger Observatory … ."2

Cronin received the Ernest Orlando Lawrence Award in 1976 for major experimental contributions to particle physics including fundamental work on weak interactions culminating in the discovery of asymmetry under time reversal.

Resources with Additional Information

Additional information about James Cronin and the charge-parity (CP) violation is available in electronic documents and on the Web.



Measurement of the Branching Ratio KLγ γ ∕ KL → 3π 0, DOE Technical Report, August 1968

Measurement of the Branching Ratio KL → 2π 0 ∕ KL → 3π 0, DOE Technical Report, August 1968

Atomic Number Dependence of Hadron Production at Large Transverse Momentum in 300 GeV Proton--Nucleus Collisions, DOE Technical Report, July 1974

Measurement of Ultracold Neutrons Produced by Using Doppler-shifted Bragg Reflection at a Pulsed-neutron Source, DOE Technical Report, 1979

Report of the Working Group on CP Violation and Rare Decays, DOE Technical Report, October 1984


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