The Sherwood Conferences were a series of classified conferences that were held between 1952 and 1958 in the United States. These conferences were a part of the United States controlled nuclear program called Project Sherwood. These conferences were established in order to entice experienced personnel to join the newly developed Project Sherwood. There were three different plasma confinement designs that were being researched in three different locations: the stellarator at Princeton Plasma Physics Laboratory, the toroidal pinch at Los Alamos National Laboratory, and the magnetic mirror at the Livermore National Laboratory. Because these individual projects operated in separate facilities, these conferences were helpful to strengthen communication of information between all three projects. [1]
The first Sherwood conference was organized by the AEC director of the Division of Research, Thomas Johnson. [2] The conference was held at the University of Denver in Denver, Colorado on June 28, 1952. To attract more experienced personnel, workers already participating on the projects attended the conference. Overall, there were about eighty scientists that attended the first conference. [3] [4]
Date | Location |
---|---|
June 28, 1952 | University of Denver, Denver, Colorado |
April 7, 1953 | University of California, Berkeley, California |
June 24, 1954 | Los Alamos, New Mexico |
October 26–27, 1954 | Princeton University, Princeton, New Jersey |
February 7–9, 1955 | University of California Radiation Laboratory, Livermore, California |
June 10–11, 1955 | Los Alamos, New Mexico |
October 17–20, 1955 | Princeton University, Princeton, New Jersey |
June 4–7, 1956 | Gatlinburg, Tennessee |
February 20–23, 1957 | Berkeley, California |
October 17–18, 1957 | Princeton, New Jersey |
February 3–6, 1958 | Washington, D.C. |
A stellarator is a plasma device that relies primarily on external magnets to confine a plasma. Scientists researching magnetic confinement fusion aim to use stellarator devices as a vessel for nuclear fusion reactions. The name refers to the possibility of harnessing the power source of the stars, such as the Sun. It is one of the earliest fusion power devices, along with the z-pinch and magnetic mirror.
A tokamak is a device which uses a powerful magnetic field to confine plasma in the shape of a torus. The tokamak is one of several types of magnetic confinement devices being developed to produce controlled thermonuclear fusion power. As of 2016, it was the leading candidate for a practical fusion reactor.
Princeton Plasma Physics Laboratory (PPPL) is a United States Department of Energy national laboratory for plasma physics and nuclear fusion science. Its primary mission is research into and development of fusion as an energy source. It is known in particular for the development of the stellarator and tokamak designs, along with numerous fundamental advances in plasma physics and the exploration of many other plasma confinement concepts.
A magnetic mirror, known as a magnetic trap in Russia and briefly as a pyrotron in the US, is a type of magnetic confinement fusion device used in fusion power to trap high temperature plasma using magnetic fields. The mirror was one of the earliest major approaches to fusion power, along with the stellarator and z-pinch machines.
Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. In a fusion process, two lighter atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices designed to harness this energy are known as fusion reactors. Research into fusion reactors began in the 1940s, but as of 2023, no device has reached net power.
This timeline of nuclear fusion is an incomplete chronological summary of significant events in the study and use of nuclear fusion.
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Project Sherwood was the codename for a United States program in controlled nuclear fusion during the period it was classified. After 1958, when fusion research was declassified around the world, the project was reorganized as a separate division within the United States Atomic Energy Commission (AEC) and lost its codename.
ZETA, short for Zero Energy Thermonuclear Assembly, was a major experiment in the early history of fusion power research. Based on the pinch plasma confinement technique, and built at the Atomic Energy Research Establishment in the United Kingdom, ZETA was larger and more powerful than any fusion machine in the world at that time. Its goal was to produce large numbers of fusion reactions, although it was not large enough to produce net energy.
Robert L. Hirsch is an American physicist who has been involved in energy issues from the late 1960s. Through the 1970s he directed the U.S. fusion energy program at a variety of government positions as responsibility for the project moved from the Atomic Energy Commission to the Energy Research and Development Administration and finally to the Department of Energy. After that time he was a senior energy program adviser for Science Applications International Corporation and is a Senior Energy Advisor at MISI and a consultant in energy, technology, and management.
Amasa Stone Bishop was an American nuclear physicist specializing in fusion physics. He received his B.S. in physics from the California Institute of Technology in 1943. From 1943 to 1946 he was a member of the staff of Radiation Laboratory at the Massachusetts Institute of Technology, where he was involved with radar research and development. Later, he became a staff member of the University of California at Berkeley from 1946 to 1950. Specializing in high energy particle work, he earned his Ph.D. in physics in 1950.
Sceptre was a series of early fusion power devices based on the Z-pinch concept of plasma confinement, built in the UK starting in 1956. They were the ultimate versions of a series of devices tracing their history to the original pinch machines, built at Imperial College London by Cousins and Ware in 1947. When the UK's fusion work was classified in 1950, Ware's team was moved to the Associated Electrical Industries (AEI) labs at Aldermaston. The team worked on the problems associated with using metal tubes with high voltages, in support of the efforts at Harwell. When Harwell's ZETA machine apparently produced fusion, AEI quickly built a smaller machine, Sceptre, to test their results. Sceptre also produced neutrons, apparently confirming the ZETA experiment. It was later found that the neutrons were spurious, and UK work on Z-pinch ended in the early 1960s.
The Astron is a type of fusion power device pioneered by Nicholas Christofilos and built at the Lawrence Livermore National Laboratory during the 1960s and 70s. Astron used a unique confinement system that avoided several of the problems found in contemporary designs like the stellarator and magnetic mirror. Development was greatly slowed by a series of changes to the design that were made with limited oversight, leading to a review committee being set up to oversee further development. The Astron was unable to meet the performance goals set for it by the committee; funding was cancelled in 1972 and development wound down in 1973. Work on similar designs appears to have demonstrated a theoretical problem in the very design that suggests it could never be used for practical generation.
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Theta-pinch, or θ-pinch, is a type of fusion power reactor design. The name refers to the configuration of currents used to confine the plasma fuel in the reactor, arranged to run around a cylinder in the direction normally denoted as theta in polar coordinate diagrams. The name was chosen to differentiate it from machines based on the pinch effect that arranged their currents running down the centre of the cylinder; these became known as z-pinch machines, referring to the Z-axis in cartesian coordinates.
Harold Ralph Lewis, Jr., was an American physicist, researcher at the Los Alamos National Laboratory, and professor at Dartmouth College. Lewis worked on Project Sherwood and conducted research in nuclear physics and plasma physics.
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