University of Michigan
University of Pennsylvania
University of Michigan
University of Pennsylvania
Julius “Jules” Halpern was born on February 4, 1912, in Norfolk, Virginia. His professional identity was closely associated with experimental nuclear and particle physics, fields in which he worked across several generations of scientific instrumentation, from cloud chambers and neutron sources to synchrotrons and high-energy accelerators. He was the father of Ralph Lawrence Halpern, an American lawyer who practiced in Buffalo, New York.
Halpern received his undergraduate and graduate training in physics at the Carnegie Institute of Technology in Pittsburgh. He earned a B.S. degree in 1933, an M.S. degree in 1935, and a Doctor of Science degree in 1938. His doctoral dissertation, The Scattering of Slow Neutrons by Liquid Ortho- and Parahydrogen, was completed under the direction of Otto Stern and was based on experimental work in the institution’s Research Laboratory of Molecular Physics. This training established the experimental foundation for his later work in neutron physics, nuclear reactions, radiation research, and accelerator-based particle physics.
Halpern began his professional scientific career at the Carnegie Institute of Technology, where he was a teaching fellow in physics from 1934 to 1936 and then worked as a research physicist in the Research Laboratory of Molecular Physics from 1936 to 1937. His early Carnegie research included measurements of slow-neutron scattering by liquid orthohydrogen and parahydrogen. From 1937 to 1940 he collaborated with H. Richard Crane at the University of Michigan on experimental nuclear physics, beta decay, gamma-ray spectra, electron and positron production, and the measurement of nuclear recoil and neutrino momentum using cloud-chamber methods. Their work provided early quantitative evidence that a third particle participates in beta decay and that the neutrino carries momentum. During the Second World War, Halpern worked as a physicist and research director at the MIT Radiation Laboratory from 1940 to 1945, contributing to classified radar-related research. After the war he joined the University of Pennsylvania, where he taught and conducted research in physics from 1947 until his death in 1972. At Penn he became a central figure in high-energy physics and served as principal investigator of the university’s high-energy research group for the Atomic Energy Commission. His program included synchrotron research and accelerator experiments at the Berkeley Bevatron, including investigations into the possible existence and properties of quarks. In 1970 he led a joint University of Pennsylvania project involving Penn and University of Cincinnati researchers and graduate students in Bevatron experiments on the K*(1420) boson and related quark phenomena. His career linked prewar neutron and nuclear experiments, wartime radiation research, and postwar accelerator-based particle physics.
Conducted pioneering experimental work with H. Richard Crane on beta decay and nuclear recoil, providing early quantitative evidence that the neutrino carries momentum.
Published a series of cloud-chamber and nuclear-physics investigations at the University of Michigan concerning gamma radiation, electron and positron production, pair conversion, and nuclear reactions.
Led University of Pennsylvania high-energy physics research supported by the Atomic Energy Commission, including synchrotron and Berkeley Bevatron experiments on the possible existence and properties of quarks.
(Doctor of Science dissertation presented to the Carnegie ...)
1938(Co-authored with I. Estermann, O. C. Simpson, and O. Ster...)
1937(Co-authored with H. Richard Crane. The paper described cl...)
1938(Co-authored with H. Richard Crane as part of Halpern’s ex...)
1939(Co-authored with H. Richard Crane. The paper examined gam...)
1939(Co-authored with H. Richard Crane and reported measuremen...)
1939(Co-authored with H. Richard Crane. The study used cloud-c...)
1939(Co-authored with H. Richard Crane. The paper extended mea...)
1939(Co-authored with N. L. Oleson, K. T. Chao, and H. Richard...)
1939(Co-authored with H. Richard Crane and N. L. Oleson. The p...)
1940The Internal Conversion Coefficient in the F19 + H1 Reaction and Measurements on the Gamma-Ray Spectrum
(Co-authored with H. Richard Crane and published in Physic...)
1939Halpern served on the University of Pennsylvania Faculty Club Committee in the 1950s and was a member of the university’s Senate Committee on Academic Freedom and Responsibility during the 1970–1971 academic year.
Halpern collaborated with H. Richard Crane at the University of Michigan on a series of cloud-chamber investigations of beta decay, nuclear recoil, gamma radiation, and electron-pair production. At Carnegie Institute of Technology, his doctoral research was directed by Otto Stern. He was the father of Ralph Lawrence Halpern, an American lawyer who practiced in Buffalo, New York.
