Robert Lyster Thornton
Encyclopedia
Robert Lyster Thornton (November 29, 1908 - September 28, 1985), was born at Wooton, Bedfordshire
, England
, the son of a mechanical engineer, Dudley L. Thornton, and his wife Katherine Foster. He was educated in Canada, where his family went in his youth, his father being employed by the Canadian Pacific Railway
. He attended McGill University
for seven years, earning the B.Sc. degree in 1930 and obtaining the Ph.D. degree in physics, under the sponsorship of Stuart Foster, in 1933. His thesis research was on atomic spectroscopy
and the Stark effect
, an area successfully cultivated by his mentor.
Thornton came to the Lawrence Radiation Laboratory
of the University of California at Berkeley in 1933 and most of his later career was connected with that Laboratory where he worked with Professor Ernest Lawrence
, the inventor of the cyclotron
. The 1930s were years of intense cyclotron development at Berkeley under Lawrence's leadership and Thornton became a prominent member of his team. Thornton worked initially on the 12-inch and 37-inch cyclotrons at Berkeley and on design of the 60-inch cyclotrons.
Toward the end of the 1930s several universities wanted to acquire a cyclotron and turned to Lawrence who often sent detailed plans to those who wanted to build one and loaned one of his collaborators to help with the work. Lawrence sent Thornton to the University of Michigan
in Ann Arbor to lead in the construction of a cyclotron, and where he was also an instructor in Physics from 1936 to 1938. During 1938-1939 he worked with physicist D.R. Colson to show the first cloud chamber picture of uranium fusion.
Thornton left Berkeley again in 1940, this time to Washington University at St. Louis, Missouri as an associate professor of physics, to head the construction of a cyclotron, one of the best of its time. This period ended in 1942 when the Rad Lab at Berkeley entered massively into the uranium isotope separation endeavor for the Manhattan Project
. Lawrence asked Thornton to return to help with development of the calutron
project, a gigantic array of modified cyclotrons adapted to the separation of uranium isotopes. In 1943 Thornton became assistant director of the Process Improvement Division of the Tennessee Eastman Corporation at Oak Ridge, Tennessee
, where the huge Y-12
plant containing hundreds of calutrons was located.
In 1945 Thornton returned to Berkeley where he led construction of the 184-inch cyclotron, the first large frequency-modulated cyclotron that used the new concept of phase stability. It was highly successful and made possible scientific advances, such as production of the first man-made pions (pi mesons), He also began his 27-year professorial affiliation with the Department of Physics of the University of California at Berkeley, as Professor of Physics. In 1948 he started regular classroom teaching of several upper-division courses in mechanics, modern physics, and electricity and magnetism. In 1954 he was appointed assistant director of the Radiation Laboratory, in 1959 associate director, and in 1967 associate director of program and planning. He was for a long time in charge of scheduling for the 184-inch cyclotron. Thornton retired in 1972.
Robert Thornton married Mary Elizabeth (Betty) Edie in 1938; their union ending at her death in 1974. They had two daughters and a son. Their oldest child, Katherine (Katy) and her bridegroom, Clarence Brodie, were killed in a private plane crash shortly after their wedding in 1966. Their daughter Margaret (Peggy) married Michael Mendeck, a petroleum engineer, in 1974; they live in Colorado with their children, Gavin and Lauren. Their son, Denis, married Carol Dodd in 1975; they have two daughters, Stephanie and Jennifer, and are both members of the teaching staff of Illinois State University at Normal, Illinois.
In 1977 Bob Thornton and Sigvor Hamre, who survives him, were married. She was the widow of Haakon Hamre, long-time professor of Scandinavian language and literature, and department chairman, in the University of California at Berkeley.
Bedfordshire
Bedfordshire is a ceremonial county of historic origin in England that forms part of the East of England region.It borders Cambridgeshire to the north-east, Northamptonshire to the north, Buckinghamshire to the west and Hertfordshire to the south-east....
, England
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
, the son of a mechanical engineer, Dudley L. Thornton, and his wife Katherine Foster. He was educated in Canada, where his family went in his youth, his father being employed by the Canadian Pacific Railway
Canadian Pacific Railway
The Canadian Pacific Railway , formerly also known as CP Rail between 1968 and 1996, is a historic Canadian Class I railway founded in 1881 and now operated by Canadian Pacific Railway Limited, which began operations as legal owner in a corporate restructuring in 2001...
. He attended McGill University
McGill University
Mohammed Fathy is a public research university located in Montreal, Quebec, Canada. The university bears the name of James McGill, a prominent Montreal merchant from Glasgow, Scotland, whose bequest formed the beginning of the university...
for seven years, earning the B.Sc. degree in 1930 and obtaining the Ph.D. degree in physics, under the sponsorship of Stuart Foster, in 1933. His thesis research was on atomic spectroscopy
Atomic spectroscopy
Atomic spectroscopy is the determination of elemental composition by its electromagnetic or mass spectrum. Atomic spectroscopy is closely related to other forms of spectroscopy. It can be divided by atomization source or by the type of spectroscopy used. In the latter case, the main division is...
and the Stark effect
Stark effect
The Stark effect is the shifting and splitting of spectral lines of atoms and molecules due to presence of an external static electric field. The amount of splitting and or shifting is called the Stark splitting or Stark shift. In general one distinguishes first- and second-order Stark effects...
, an area successfully cultivated by his mentor.
Thornton came to the Lawrence Radiation Laboratory
Lawrence Livermore National Laboratory
The Lawrence Livermore National Laboratory , just outside Livermore, California, is a Federally Funded Research and Development Center founded by the University of California in 1952...
of the University of California at Berkeley in 1933 and most of his later career was connected with that Laboratory where he worked with Professor Ernest Lawrence
Ernest Lawrence
Ernest Orlando Lawrence was an American physicist and Nobel Laureate, known for his invention, utilization, and improvement of the cyclotron atom-smasher beginning in 1929, based on his studies of the works of Rolf Widerøe, and his later work in uranium-isotope separation for the Manhattan Project...
, the inventor of the cyclotron
Cyclotron
In technology, a cyclotron is a type of particle accelerator. In physics, the cyclotron frequency or gyrofrequency is the frequency of a charged particle moving perpendicularly to the direction of a uniform magnetic field, i.e. a magnetic field of constant magnitude and direction...
. The 1930s were years of intense cyclotron development at Berkeley under Lawrence's leadership and Thornton became a prominent member of his team. Thornton worked initially on the 12-inch and 37-inch cyclotrons at Berkeley and on design of the 60-inch cyclotrons.
Toward the end of the 1930s several universities wanted to acquire a cyclotron and turned to Lawrence who often sent detailed plans to those who wanted to build one and loaned one of his collaborators to help with the work. Lawrence sent Thornton to the University of Michigan
University of Michigan
The University of Michigan is a public research university located in Ann Arbor, Michigan in the United States. It is the state's oldest university and the flagship campus of the University of Michigan...
in Ann Arbor to lead in the construction of a cyclotron, and where he was also an instructor in Physics from 1936 to 1938. During 1938-1939 he worked with physicist D.R. Colson to show the first cloud chamber picture of uranium fusion.
Thornton left Berkeley again in 1940, this time to Washington University at St. Louis, Missouri as an associate professor of physics, to head the construction of a cyclotron, one of the best of its time. This period ended in 1942 when the Rad Lab at Berkeley entered massively into the uranium isotope separation endeavor for the Manhattan Project
Manhattan Project
The Manhattan Project was a research and development program, led by the United States with participation from the United Kingdom and Canada, that produced the first atomic bomb during World War II. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the US Army...
. Lawrence asked Thornton to return to help with development of the calutron
Calutron
A calutron is a mass spectrometer used for separating the isotopes of uranium. It was developed by Ernest O. Lawrence during the Manhattan Project and was similar to the cyclotron invented by Lawrence. Its name is a concatenation of Cal. U.-tron, in tribute to the University of California,...
project, a gigantic array of modified cyclotrons adapted to the separation of uranium isotopes. In 1943 Thornton became assistant director of the Process Improvement Division of the Tennessee Eastman Corporation at Oak Ridge, Tennessee
Oak Ridge, Tennessee
Oak Ridge is a city in Anderson and Roane counties in the eastern part of the U.S. state of Tennessee, about west of Knoxville. Oak Ridge's population was 27,387 at the 2000 census...
, where the huge Y-12
Y-12 National Security Complex
The Y-12 National Security Complex is a United States Department of Energy National Nuclear Security Administration facility located in Oak Ridge, Tennessee, near the Oak Ridge National Laboratory...
plant containing hundreds of calutrons was located.
In 1945 Thornton returned to Berkeley where he led construction of the 184-inch cyclotron, the first large frequency-modulated cyclotron that used the new concept of phase stability. It was highly successful and made possible scientific advances, such as production of the first man-made pions (pi mesons), He also began his 27-year professorial affiliation with the Department of Physics of the University of California at Berkeley, as Professor of Physics. In 1948 he started regular classroom teaching of several upper-division courses in mechanics, modern physics, and electricity and magnetism. In 1954 he was appointed assistant director of the Radiation Laboratory, in 1959 associate director, and in 1967 associate director of program and planning. He was for a long time in charge of scheduling for the 184-inch cyclotron. Thornton retired in 1972.
Robert Thornton married Mary Elizabeth (Betty) Edie in 1938; their union ending at her death in 1974. They had two daughters and a son. Their oldest child, Katherine (Katy) and her bridegroom, Clarence Brodie, were killed in a private plane crash shortly after their wedding in 1966. Their daughter Margaret (Peggy) married Michael Mendeck, a petroleum engineer, in 1974; they live in Colorado with their children, Gavin and Lauren. Their son, Denis, married Carol Dodd in 1975; they have two daughters, Stephanie and Jennifer, and are both members of the teaching staff of Illinois State University at Normal, Illinois.
In 1977 Bob Thornton and Sigvor Hamre, who survives him, were married. She was the widow of Haakon Hamre, long-time professor of Scandinavian language and literature, and department chairman, in the University of California at Berkeley.