Jack Steinberger
Encyclopedia
Jack Steinberger is a German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

-American
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 currently residing near Geneva, Switzerland. He co-discovered the muon neutrino
Muon neutrino
The muon neutrino is a subatomic lepton elementary particle which has the symbol and no net electric charge. Together with the muon it forms the second generation of leptons, hence its name muon neutrino. It was first hypothesized in the early 1940s by several people, and was discovered in 1962 by...

, along with Leon Lederman and Melvin Schwartz
Melvin Schwartz
Melvin Schwartz was an American physicist. He shared the 1988 Nobel Prize in Physics with Leon M. Lederman and Jack Steinberger for their development of the neutrino beam method and their demonstration of the doublet structure of the leptons through the discovery of the muon neutrino.He grew up in...

, for which they were given the 1988 Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...

.

Life

Steinberger was born in the city of Bad Kissingen
Bad Kissingen
Bad Kissingen is a spa town in the Bavarian region of Lower Franconia and is the seat of the district Bad Kissingen. Situated to the south of the Rhön Mountains on the Franconian Saale river, it is a world-famous health resort.- Town structure :...

 in Bavaria
Bavaria
Bavaria, formally the Free State of Bavaria is a state of Germany, located in the southeast of Germany. With an area of , it is the largest state by area, forming almost 20% of the total land area of Germany...

, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

, in 1921. The rise of the Nazi
Nazism
Nazism, the common short form name of National Socialism was the ideology and practice of the Nazi Party and of Nazi Germany...

 party in Germany, with its open anti-Semitism
Anti-Semitism
Antisemitism is suspicion of, hatred toward, or discrimination against Jews for reasons connected to their Jewish heritage. According to a 2005 U.S...

, prompted his parents to send him out of the country.

Steinberger emigrated to the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 at the age of 13, making the trans-Atlantic trip with his brother Herbert. Barnett Farroll cared for him as a foster child, the connection was made by Jewish charities in the United States. During this period, Steinberger attended New Trier Township High School, in Winnetka, Illinois
Winnetka, Illinois
Winnetka is an affluent North Shore village located approximately north of downtown Chicago in Cook County, Illinois. Winnetka was featured on the list of America's 25 top-earning towns and "one of the best places to live" by CNN Money in 2011...

.

Steinberger studied chemical engineering at Armour Institute of Technology (now Illinois Institute of Technology
Illinois Institute of Technology
Illinois Institute of Technology, commonly called Illinois Tech or IIT, is a private Ph.D.-granting university located in Chicago, Illinois, with programs in engineering, science, psychology, architecture, business, communications, industrial technology, information technology, design, and law...

) but left after his scholarship ended to help supplement his family's income. He obtained a bachelor's degree in Chemistry from the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

, in 1942. Shortly thereafter, he joined the Signal Corps at MIT. With the help of the G.I. Bill, he returned to graduate studies at the University of Chicago
University of Chicago
The University of Chicago is a private research university in Chicago, Illinois, USA. It was founded by the American Baptist Education Society with a donation from oil magnate and philanthropist John D. Rockefeller and incorporated in 1890...

 in 1946, where he studied under Edward Teller
Edward Teller
Edward Teller was a Hungarian-American theoretical physicist, known colloquially as "the father of the hydrogen bomb," even though he did not care for the title. Teller made numerous contributions to nuclear and molecular physics, spectroscopy , and surface physics...

 and Enrico Fermi
Enrico Fermi
Enrico Fermi was an Italian-born, naturalized American physicist particularly known for his work on the development of the first nuclear reactor, Chicago Pile-1, and for his contributions to the development of quantum theory, nuclear and particle physics, and statistical mechanics...

. His Ph.D. thesis concerned the energy spectrum of electrons emitted in muon
Muon
The muon |mu]] used to represent it) is an elementary particle similar to the electron, with a unitary negative electric charge and a spin of ½. Together with the electron, the tau, and the three neutrinos, it is classified as a lepton...

 decay
Particle decay
Particle decay is the spontaneous process of one elementary particle transforming into other elementary particles. During this process, an elementary particle becomes a different particle with less mass and an intermediate particle such as W boson in muon decay. The intermediate particle then...

; his results showed that this was a three-body decay, and implied the participation of two neutral particle in the decay (later identified as the electron
Electron neutrino
The electron neutrino is a subatomic lepton elementary particle which has no net electric charge. Together with the electron it forms the first generation of leptons, hence its name electron neutrino...

  and muon
Muon neutrino
The muon neutrino is a subatomic lepton elementary particle which has the symbol and no net electric charge. Together with the muon it forms the second generation of leptons, hence its name muon neutrino. It was first hypothesized in the early 1940s by several people, and was discovered in 1962 by...

  neutrinos) rather than one.

Early career

After receiving his doctorate, Steinberger attended the Institute for Advanced Study
Institute for Advanced Study
The Institute for Advanced Study, located in Princeton, New Jersey, United States, is an independent postgraduate center for theoretical research and intellectual inquiry. It was founded in 1930 by Abraham Flexner...

 in Princeton
Princeton, New Jersey
Princeton is a community located in Mercer County, New Jersey, United States. It is best known as the location of Princeton University, which has been sited in the community since 1756...

 for a year. In 1949 he published a calculation of the lifetime of the neutral pion
Pion
In particle physics, a pion is any of three subatomic particles: , , and . Pions are the lightest mesons and they play an important role in explaining the low-energy properties of the strong nuclear force....

, which anticipated the study of anomalies in quantum field theory.

Following Princeton, Steinberger went to the Radiation Lab at the University of California at Berkeley, where he performed an experiment which demonstrated the production of neutral pions and their decay to photon pairs. This experiment utilized the 330 MeV synchrotron and the newly-invented scintillation counters. Despite this and other achievements, he was asked to leave the Radiation Lab at Berkeley due to his refusal to sign the so-called Non-Communist Oath.

Steinberger accepted a faculty position at Columbia in 1950. The newly commissioned meson
Meson
In particle physics, mesons are subatomic particles composed of one quark and one antiquark, bound together by the strong interaction. Because mesons are composed of sub-particles, they have a physical size, with a radius roughly one femtometer: 10−15 m, which is about the size of a proton...

 beam at Nevis Labs
Nevis Labs
Nevis Labs stands for one of the following known organizations:#Nevis Laboratories -- a research center specializing in the preparation, design, and construction of high-energy particle and nuclear experiments and equipment....

 provided the tool for several important experiments. Measurements of the production cross section of pions on various nuclear targets showed that the pion has odd parity. A direct measurement of the production of pions on a liquid hydrogen
Liquid hydrogen
Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...

 target, then not a common tool, provided the data needed to show that the pion has spin zero. The same target was used to observe the relative rare decay of neutral pions to a photon, an electron and a positron
Positron
The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of ½, and has the same mass as an electron...

. A related experiment measured the mass difference between the charged and neutral pions based on the angular correlation between the neutral pions produced when the negative pion is captured by the proton in the hydrogen nucleus. Other important experiments studied the angular correlation between electron-positron pairs in neutral pion decays, and established the rare decay of a charged pion to an electron and neutrino; the latter required use of a liquid-hydrogen bubble chamber
Bubble chamber
A bubble chamber is a vessel filled with a superheated transparent liquid used to detect electrically charged particles moving through it. It was invented in 1952 by Donald A. Glaser, for which he was awarded the 1960 Nobel Prize in Physics...

.

Investigations of strange particles

During 1954–1955, Steinberger contributed to the development of the bubble chamber
Bubble chamber
A bubble chamber is a vessel filled with a superheated transparent liquid used to detect electrically charged particles moving through it. It was invented in 1952 by Donald A. Glaser, for which he was awarded the 1960 Nobel Prize in Physics...

 with the construction of a 15 cm device for use with the Cosmotron
Cosmotron
The Cosmotron was a particle accelerator, specifically a proton synchrotron, at Brookhaven National Laboratory. Its construction was approved by the U.S. Atomic Energy Commission in 1948, it reached its full energy in 1953, and it continued running until 1968...

 at Brookhaven National Laboratory
Brookhaven National Laboratory
Brookhaven National Laboratory , is a United States national laboratory located in Upton, New York on Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base...

. The experiment used a pion beam to produce pairs of hadrons with strange quarks in order to elucidate the puzzling production and decay properties of these particles. Somewhat later, in 1956, a 30 cm chamber outfitted with three cameras was used in the discovery of the neutral Sigma hyperon
Sigma baryon
The Sigma baryons are a family of subatomic hadron particles which have a +2, +1 or -1 elementary charge or are neutral. They are baryons containing three quarks: two up and/or down quarks, and one third quark, which can be either a strange , a charm , a bottom or a top quark...

 and a measurement of its mass. This observation was important for confirming the existence of the SU(3) flavor symmetry which hypothesizes the existence of the strange quark.

An important characteristic of the weak interaction
Weak interaction
Weak interaction , is one of the four fundamental forces of nature, alongside the strong nuclear force, electromagnetism, and gravity. It is responsible for the radioactive decay of subatomic particles and initiates the process known as hydrogen fusion in stars...

 is its violation of parity symmetry. This characteristic was established through the measurement of the spins and parities of many hyperons. Steinberger and his collaborators contributed several such measurements using large (75 cm) liquid-hydrogen bubble chambers and separated hadron beams at Brookhaven. One example is the measurement of the invariant mass distribution of electron-positron pairs produced in the decay of Sigma-zero hyperons
Sigma baryon
The Sigma baryons are a family of subatomic hadron particles which have a +2, +1 or -1 elementary charge or are neutral. They are baryons containing three quarks: two up and/or down quarks, and one third quark, which can be either a strange , a charm , a bottom or a top quark...

 to Lambda-zero hyperons.

Neutrinos and the weak neutral current

In the 1960s, the emphasis in the study of the weak interaction shifted from strange particles to neutrinos. Leon Lederman, Steinberger and Schwartz
Melvin Schwartz
Melvin Schwartz was an American physicist. He shared the 1988 Nobel Prize in Physics with Leon M. Lederman and Jack Steinberger for their development of the neutrino beam method and their demonstration of the doublet structure of the leptons through the discovery of the muon neutrino.He grew up in...

 built large spark chambers at Nevis Lab and exposed them in 1961 to neutrinos produced in association with muons in the decays of charged pions and kaons. They used the Alternating Gradient Synchrotron
Alternating Gradient Synchrotron
The Alternating Gradient Synchrotron is a particle accelerator located at the Brookhaven National Laboratory in Long Island, New York, USA....

 (AGS) at Brookhaven, and obtained a number of convincing events in which muons were produced, but no electrons. This result, for which they received the Nobel Prize in 1988, proved the existence of a type of neutrino associated with the muon, distinct from the neutrino produced in beta decay.

Study of CP violation

The CP violation
CP violation
In particle physics, CP violation is a violation of the postulated CP-symmetry: the combination of C-symmetry and P-symmetry . CP-symmetry states that the laws of physics should be the same if a particle were interchanged with its antiparticle , and left and right were swapped...

 (charge conjugation and parity
Parity (physics)
In physics, a parity transformation is the flip in the sign of one spatial coordinate. In three dimensions, it is also commonly described by the simultaneous flip in the sign of all three spatial coordinates:...

) was established in the neutral kaon system in 1964. Steinberger recognized that the phenomenological parameter epsilon (ε) which quantifies the degree of CP violation could be measured in interference phenomena (See CP violation). In collaboration with Carlo Rubbia
Carlo Rubbia
Carlo Rubbia Knight Grand Cross is an Italian particle physicist and inventor who shared the Nobel Prize in Physics in 1984 with Simon van der Meer for work leading to the discovery of the W and Z particles at CERN.-Biography:...

, he performed an experiment while on sabbatical at CERN
CERN
The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...

 during 1965 which demonstrated robustly the expected interference effect, and also measured precisely the difference in mass of the short-lived and long-lived neutral kaon masses.

Back in the United States, Steinberger conducted an experiment at Brookhaven to observe CP violation in the semi-leptonic decays of neutral kaons. The charge asymmetry relates directly to the epsilon parameter, which was thereby measured precisely. This experiment also allowed the deduction of the phase of epsilon, and confirmed that CPT
CPT symmetry
CPT symmetry is a fundamental symmetry of physical laws under transformations that involve the inversions of charge, parity, and time simultaneously.-History:...

 is a good symmetry of nature.

CERN

In 1968, Steinberger left Columbia University and accepted a position as a department director at CERN
CERN
The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...

. He constructed an experiment there utilizing multi-wire proportional chambers (MWPC), recently invented by Georges Charpak
Georges Charpak
Georges Charpak was a French physicist who was awarded the Nobel Prize in Physics in 1992.-Life:Georges Charpak was born to Jewish family in the village of Dąbrowica in Poland . Charpak's family moved from Poland to Paris when he was seven years old...

. The MWPC's, augmented by micro-electronic amplifiers, allowed much larger samples of events to be recorded. Several results for neutral kaons were obtained and published in the early 1970s, including the observation of the rare decay of the neutral kaon to a muon pair, the time-dependence of the asymmetry for semi-leptonic decays, and a more precise measurement of the neutral kaon mass difference. A new era in experimental technique was opened.

These new techniques proved crucial for the first demonstration of direct CP-violation. The NA31 experiment at CERN was built in the early 1980s using the CERN SPS 400 GeV proton synchrotron
Super Proton Synchrotron
The Super Proton Synchrotron is a particle accelerator of the synchrotron type at CERN. It is housed in a circular tunnel, in circumference, straddling the border of France and Switzerland near Geneva, Switzerland. The SPS was designed by a team led by John Adams, director-general of what was...

. Aside from banks of MWPC's and a hadron calorimeter, it featured a liquid argon electromagnetic calorimeter with exceptional spatial and energy resolution. NA31 showed that direct CP violation is real.

Nobel Prize

Jack Steinberger was awarded the Nobel Prize in Physics
Nobel Prize in Physics
The Nobel Prize in Physics is awarded once a year by the Royal Swedish Academy of Sciences. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901; the others are the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and...

 in the year 1988, "for the neutrino beam method and the demonstration of the doublet structure of the leptons through the discovery of the muon neutrino". He shares this prize with Leon M. Lederman
Leon M. Lederman
Leon Max Lederman is an American experimental physicist and Nobel Prize in Physics laureate for his work with neutrinos. He is Director Emeritus of Fermi National Accelerator Laboratory in Batavia, Illinois, USA...

 and Melvin Schwartz
Melvin Schwartz
Melvin Schwartz was an American physicist. He shared the 1988 Nobel Prize in Physics with Leon M. Lederman and Jack Steinberger for their development of the neutrino beam method and their demonstration of the doublet structure of the leptons through the discovery of the muon neutrino.He grew up in...

. At the time, all three experimenters were at Columbia University
Columbia University
Columbia University in the City of New York is a private, Ivy League university in Manhattan, New York City. Columbia is the oldest institution of higher learning in the state of New York, the fifth oldest in the United States, and one of the country's nine Colonial Colleges founded before the...

.

The experiment used charged pion
Pion
In particle physics, a pion is any of three subatomic particles: , , and . Pions are the lightest mesons and they play an important role in explaining the low-energy properties of the strong nuclear force....

 beams generated with the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory
Brookhaven National Laboratory
Brookhaven National Laboratory , is a United States national laboratory located in Upton, New York on Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base...

. The pions decayed to muons which were detected in front of a steel wall; the neutrinos were detected in spark chambers installed behind the wall. The coincidence of muons and neutrinos demonstrated that a second kind of neutrino was created in association with muons. Subsequent experiments proved this neutrino to be distinct from the first kind (electron-type). Steinberger, Lederman and Schwartz published their work in Physical Review Letters in 1962.

He gave his Nobel medal to New Trier High School
New Trier High School
New Trier High School is a public four-year high school , with its major campus located in Winnetka, Illinois, USA, and a second campus in Northfield, Illinois, with freshman classes and district administration...

 in Winnetka, Illinois
Winnetka, Illinois
Winnetka is an affluent North Shore village located approximately north of downtown Chicago in Cook County, Illinois. Winnetka was featured on the list of America's 25 top-earning towns and "one of the best places to live" by CNN Money in 2011...

 (USA), of which he is an alumnus.

Publications

  • Steinberger, J. & A. S. Bishop. "The Detection of Artificially Produced Photomesons with Counters", Radiation Laboratory, University of California-Berkeley, United States Department of Energy
    United States Department of Energy
    The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

     (through predecessor agency the Atomic Energy Commission
    United States Atomic Energy Commission
    The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

    ), (March 8, 1950).
  • Steinberger, J., W. K. H. Panofsky & J. Steller. "Evidence for the Production of Neutral Mesons by Photons", Radiation Laboratory, University of California-Berkeley, United States Department of Energy
    United States Department of Energy
    The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

     (through predecessor agency the Atomic Energy Commission
    United States Atomic Energy Commission
    The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

    ), (April 1950).
  • Panofsky, W. K. H., J. Steinberger & J. Steller. "Further Results on the Production of Neutral Mesons by Photons", Radiation Laboratory, University of California-Berkeley, United States Department of Energy
    United States Department of Energy
    The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

     (through predecessor agency the Atomic Energy Commission
    United States Atomic Energy Commission
    The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

    ), (October 1, 1950).
  • Steinberger, J. "Experimental Survey of Strange Particle Decays", Columbia University, Nevis Laboratories, United States Department of Energy
    United States Department of Energy
    The United States Department of Energy is a Cabinet-level department of the United States government concerned with the United States' policies regarding energy and safety in handling nuclear material...

     (through predecessor agency the Atomic Energy Commission
    United States Atomic Energy Commission
    The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...

    ), (June 1964).

External links

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