Elementary-Particle Physics (1986) / Chapter Skim
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7 Interactions with Other Areas of Physics and Technology
7 Interactions with Other Areas of Physics and Technology
Pages 157-171
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From page 157... ...
The foremost example is the particle accelerator itself, some of whose applications are described below in the section on Other Applications of Accelerators. The second way that elementary-particle physics interacts with technology is that technology from outside particle physics is stimulated and developed during the design and construction of particle-physics accelerators and detectors.
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From page 158... ...
The successes mentioned above illustrate the principles enabling big bang cosmology and particle physics to be interrelated. Our present understanding of particle physics enables us to extrapolate the Hubble expansion of the universe backward to earlier times and higher temperatures and to calculate the abundances of other elementaryparticle relics from the big bang.
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From page 159... ...
Grand unified theories also predict the existence of magnetic monopoles potential cosmological relics which, if they exist, could invalidate current cosmological theories. Their masses of 10'6 GeV or more
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From page 160... ...
Some simple arguments suggest that unacceptably many grand unified monopoles would have been produced in the conventional big bang cosmology, a difficulty that was a stimulus for the proposal of so-called inflationary cosmology. According to this idea, there may have been an early epoch in the history of the universe during which it expanded exponentially, driven by the energy released when there was a change or transition in the state of matter.
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From page 161... ...
Above 10'6 eV, the integrated primary cosmic-ray flux is only one per square meter per year. Other areas addressed by cosmic-ray experiments that overlap astrophysics, particle physics, and nuclear physics include the search for antimatter in cosmic rays and the study of nucleus-nucleus interactions at very high energy.
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From page 162... ...
Low- and medium-energy accelerators used by the nuclearphysics community include meson factories, which produce the most intense beams of protons, pions, and muons, and reactors, which produce the highest fluxes of neutrinos. Some special questions in particle physics must be explored with beams of these kinds.
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From page 163... ...
In this central region large densities can be found, sufficient for Reconfinement to occur. These large usable energies await the construction of a new accelerator, called by the nuclear science community the Relativistic Nuclear Collider (RNC)
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From page 164... ...
Deviation from the results expected from pointlike particles provides insights into the structure and interaction of the pion with leptons. Another use of spectroscopy has been the insertion of muons, pions, and kaons into the innermost electron orbits of nuclei to provide, via x-ray spectroscopy, a measure of the electric-field structure in the neighborhood of the nucleus and also to provide highprecision mass measurements of kaons and pions.
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From page 165... ...
Here we sketch some of the topics in which concepts and techniques of elementary-particle theory enrich condensed-matter physics and also some of the topics where ideas of condensed-matter physics illuminate particle physics. In the late 1950s, the techniques of quantum field theory used in particle physics started to be employed in condensed-matter physics with outstanding results.
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From page 166... ...
OTHER APPLICATIONS OF ACCELERATORS In this section we give some examples of how accelerators have been extended in their applications to other kinds of research and other kinds of technology. Synchrotron Radiation The foremost example of the application of accelerators is the use of circular electron accelerators to produce synchrotron radiation.
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From page 167... ...
As ~ high-energy electron moves in a circular orbit it emits an intense beam of x rays called synchrotron radiation. Synchrotron radiation is used for research in many scientific and technical fields: for example.
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From page 168... ...
Therefore modern synchrotron radiation accelerators have devices called wigglers or undulators introduced in the path of the electrons. These devices shake the electron as it moves through them, causing strong acceleration and the emission of intense synchrotron radiation in particularly desirable frequency ranges.
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From page 169... ...
Reactors are still the major source, but spallation neutron sources that use technically advanced proton accelerators are coming into increasing use because they can provide more-intense and higher-energy neutron beams. In a spallation source, a proton beam from a rapid cycling synchrotron bombards a uranium or other heavy-element target, providing a neutron beam.
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From page 170... ...
The most striking example is the recent construction of the Fermilab Tevatron accelerator, which uses about 1000 superconducting magnets. The liquid-helium refrigeration system used to cool those magnets is the largest in the world.
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From page 171... ...
Superconducting magnet technology is another example. These magnets as used in the Tevatron and, as proposed for use in the Superconducting Super Collider (SSC)
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