- Person
- Jack Steinberger
- Lived
- 1921–2020
- Field
- Particle physics
- From
- German-born American
The story
Jack Steinberger was born in 1921 in Bad Kissingen, Bavaria, the son of the cantor and religious teacher of the town’s small Jewish community. In 1934, after Nazi laws shut Jewish children out of higher education, he was sent to the United States through an American Jewish charity scheme for 300 refugee children, and his foster father later helped his parents escape in 1938. He studied under Enrico Fermi in Chicago and joined Columbia University in 1950.
Neutrinos are almost ghostly particles. They have no electric charge, barely interact with matter and can pass through the whole Earth. In 1961, at the suggestion of Melvin Schwartz, Steinberger, Schwartz, Leon Lederman and their colleagues used the new Alternating Gradient Synchrotron at Brookhaven National Laboratory to make neutrinos in quantity. Protons from the accelerator produced pions, which decayed in flight into muons and neutrinos. A steel wall stopped everything except the neutrinos, which passed on into large spark chambers. Hundreds of billions of neutrinos passed through, and only a handful struck atoms in the chambers.
When they did, they produced muons, but not electrons. That showed the neutrinos made alongside muons were a distinct type, the muon neutrino, different from the electron neutrino produced in radioactive beta decay. The result, published in 1962, revealed that the basic particles of matter come in matched pairs, or families, an idea at the heart of today’s Standard Model of particle physics.
The experiment also invented a method. Because neutrinos interact so rarely, a single neutrino could pass through light-years of lead, so the team compensated with an intense beam. The Nobel committee later compared neutrino beams to X-rays that reveal a skeleton: they can probe the hard inner parts of the proton. Steinberger went on to use them at CERN in the 1970s and 1980s in the CDHS experiment, which measured the structure of protons and neutrons and gave quantitative support to the quark model and to quantum chromodynamics.
Steinberger, Lederman and Schwartz shared the 1988 Nobel Prize in Physics for the neutrino beam method and the discovery of the muon neutrino.
Why it matters
Neutrino beams, first made by Steinberger and his colleagues, remain a basic tool of physics, used today in large international experiments that study how neutrinos change type and what that says about the origin of matter.
About Jack Steinberger
Child refugee from Nazi Germany who co-discovered the muon neutrino, made neutrino beams a tool for seeing inside matter and led CERN experiments confirming the Standard Model. Nobel Prize 1988.
Sources
- Jack Steinberger, Biographical NobelPrize.org
- Jack Steinberger Jewish Virtual Library
- Jack Steinberger 1921–2020 CERN Courier
- Jack Steinberger Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.