Nuclear Physics Exploring the Heart of Matter (2013) / Chapter Skim
Currently Skimming:
3 Societal Applications and Benefits
3 Societal Applications and Benefits
Pages 153-181
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 153... ...
As an example, particle beams from accelerators are used to process, treat or inspect a wide range of products with a collective value of more than $500 billion.1 At the same time, approximately 23 million nuclear medicine procedures are carried out each year in the United States to diagnose and treat cancers, cardiovascular disease, and certain neurological disorders. In the future, basic nuclear science will be a key discipline that provides ideas and insights leading to the intellectual properties and patents with which venture capitalists and entrepreneurs will shape the economies of the future.
|
From page 154... ...
Of the 23 million nuclear medicine imaging and therapeutic procedures performed each year in the United States, typically 40-50 percent are for cardiac applications, while 25-40 percent are for cancer identification and therapy. In addition, nuclear medicine procedures are used to diagnose Alzheimer's disease, treat hyperthyroidism, assess coronary artery disease, localize tumors, and diagnose pulmonary emboli.
|
From page 155... ...
. SOURCE: Courtesy of Don Wilson, British Columbia Cancer Agency.
|
From page 156... ...
When the radioactive nuclei decay, the radiation they produce loses energy quickly and because it does not travel far, a lethal dose of radiation is delivered only to adjoining tumor cells. By careful construction of the targeting molecule, the radioactive nuclei will pass through the body quickly if they do not bind to tumor cells, thus minimizing the exposure of healthy tissue to the high-energy transfer radiation.
|
From page 157... ...
degrees from Simon Fraser University, British Columbia, she pursued research into the production of rhenium-186 of high specific activity to enhance the therapeutic efficacy of this promising radionuclide. After concluding that accelerator production was not optimal, she focused on increasing specific activity of rhenium-186, produced in a reactor by the 185Re(n,g)
|
From page 158... ...
will be capable of produc ing shorter-lived isotopes of key elements for more rapid dose kinetics and new medical applications. Future Technologies in Nuclear Medicine The future impact of nuclear science on medical science is difficult to predict.
|
From page 159... ...
Protecting Our Borders from Proliferation of Nuclear Materials Border Detection of Nuclear Contraband The priority mission of our nation's Border Patrol is preventing terrorists and terrorists' weapons, including weapons of mass destruction, from entering the United States. Currently there are radiation portal monitors installed at approxi mately 300 ports of entry.
|
From page 160... ...
. Cosmic ray muons can therefore be used as an active interrogation probe of nuclear materials by detecting muons above and below a truck.
|
From page 161... ...
Current uncertainties on the important fission cross sections for stockpile stew ardship are on the order of 2 to 3 percent. In the case of plutonium-239, it would
|
From page 162... ...
Such measurements of fission probabilities and properties are important in a wide range of disciplines including nuclear energy, nuclear forensics, national security, and basic nuclear science. SOURCE: Courtesy of M
|
From page 163... ...
DANCE is also used to measure neutron cross sections on unstable targets important for s-process nucleosynthesis. The extreme conditions in a nuclear explosion result in many of the reactions taking place on unstable nuclei.
|
From page 164... ...
164 Nuclear Physics FIGURE 3.5 Understanding the growth of instabilities in shocked material is a major area of research that is being probed with proton radiography. Shown is a comparison of a proton radiograph of spikes and bubbles that are formed by the growth of Rayleigh-Taylor instabilities of a shocked tin surface (top)
|
From page 165... ...
Nuclear forensics comprises the technical means and set of scientific capabilities that, in the event of an attack, would be used to answer these questions. Nuclear scientists and the tools of nuclear science are keys to addressing the challenges of nuclear forensics, as described in detail in the Nuclear Forensics highlight between Chapters 5 and 6.
|
From page 166... ...
, displayed in Figure 3.6, to measure the decay heat of fission products. MTAS complements other instruments designed to directly measure neutron emissions following beta decay of fission fragments, neutrons that contribute to the neutron budget in a reactor and help to ensure stable reactor operation.
|
From page 167... ...
Fission cross sections are considerably less well known at fast reactor energies than at thermal energies. And the situation is most serious for the transuranic fuels.
|
From page 168... ...
For several key nuclides that have longer half-lives, FRIB will provide separated samples that can be used to measure neutron capture probabilities at neutron beam facilities. For isotopes with shorter lifetimes, indirect reaction measurements at FRIB will provide information to help constrain theo retical models for neutron-capture probabilities, using techniques that will also advance basic nuclear science and nuclear astrophysics.
|
From page 169... ...
The National Ignition Facility produces plasmas via inertial confinement fusion that are comparable to the interior of the sun. SOURCE: Courtesy of the Contemporary Physics Edu cation Project.
|
From page 170... ...
from the capsule, will be capable of imaging neutrons from capsules that burned as few as 1014 d + t reactions, as shown in Figure 3.8. INNOVATIONS IN TECHNOLOGIES AND APPLICATIONS OF NUCLEAR SCIENCE Nuclear physics is fundamentally cross-disciplinary in nature, providing experimental and theoretical tools and concepts for countless other sciences and
|
From page 171... ...
Nuclear science has and will continue to play a substantial role in developing solutions for energy, climate, and environmental challenges. Further, the primary tools of modern nuclear science -- accelerators and computers -- have spawned many applications and economic benefits, some of which are discussed here.
|
From page 172... ...
In the United States, partnerships between industry and nuclear science labo ratories have led to new accelerator developments for medical applications. For example, the National Superconducting Cyclotron Laboratory (NSCL)
|
From page 173... ...
Free-Electron Lasers A free-electron laser (FEL) is a powerful source of coherent electromagnetic radiation that is produced by a relativistic electron beam propagating through a periodic magnetic field (see Figure 3.9)
|
From page 174... ...
The electron beam periodically varying magnet field of an undulator magnet. Microbunching inside the electron beam at a spacing equal to that of the light's wavelength enables electrons to radiate coherently in order to establish lasing.
|
From page 175... ...
Recently, the LHC, which enables particle and heavy-ion nuclear physics research at the energy frontier, has reached unprecedented volumes of data and requirements for data transfer rates and data processing power. This has led to the development of technology that allows extraordinary data transfer rates at large distances.
|
From page 176... ...
Displayed are lattice QCD calculations of the transverse charge distributions of a proton (lower left) and a neutron (lower right)
|
From page 177... ...
In addition to lattice QCD calculations, these supercomputers have been just as successful in simulating exploding stars or nuclear reactors, both of which require enormous computing power. Climate science researchers at BNL are using a Blue Gene named New York Blue to make significant progress in understand ing today's climate and to better predict climate evolution.
|
From page 178... ...
Helping to Understand Climate Effects One Nucleus at a Time Applications of nuclear techniques are used to advance other scientific disci plines, including climate science, cosmochemistry, geochronology, paleoclimate, paleo-oceanography, and geomorphology. Since 1949, when Willard Libby first demonstrated carbon dating, the field of trace analyses of long-lived cosmogenic isotopes has steadily grown.
|
From page 179... ...
, two methods previously developed by nuclear physicists, ATTA is the newest method to detect tracers with an isotopic abundance at parts per trillion. Using ATTA, krypton-81 atoms in environmental samples can now be counted and the isotopic abundance of krypton-81 measured.
|
From page 180... ...
Copyright 2004 American Geophysical Union. Reproduced/modified by permission of American Geophysical Union.
|
From page 181... ...
However, its extremely low concentration (argon-39/Ar = 8.1 × 10–16) , coupled to its long half-life, makes it impossible to measure the argon-39 decay in any sample of reasonable size.4 AMS using the ATLAS heavy ion accelerator at Argonne National Laboratory has been successful in separating argon-39 from its ubiquitous potassium-39 iso baric background, the latter being 6-7 orders of magnitude more intense.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.