ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 ANS Winter Conference & Expo
November 15–18, 2026
Phoenix, AZ|Arizona Grand Resort & Spa
Latest Magazine Issues
Aug 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
October 2026
Nuclear Technology
September 2026
Fusion Science and Technology
August 2026
Latest News
What’s reshaping nuclear licensing and compliance today?
Mark Reidmeyer
It is the convergence of urgency, innovation, and modernization that is reshaping nuclear licensing and compliance today.
For decades, nuclear licensing operated in a relatively stable environment built around large light water reactors, predictable review cycles, and well-established regulatory pathways. Today, that model is evolving rapidly. Advanced reactors, AI-enabled tools, digital engineering platforms, grid reliability concerns, and aggressive decarbonization goals are all pushing the industry—and regulators—to move faster and think differently.
Mojtaba Taherzadeh, Peter J. Gingo
Nuclear Technology | Volume 15 | Number 3 | September 1972 | Pages 396-410
Technical Paper | Fuel | doi.org/10.13182/NT72-A16037
Articles are hosted by Taylor and Francis Online.
The major sources of neutrons from plutonium dioxide nuclear fuel are considered in detail. These sources include spontaneous fission of several of the plutonium isotopes, (α,n) reactions with low Z impurities in the fuel, and (α,n) reactions with 180. For spontaneous fission neutrons a value of (1.95 ± 0.07) × 103 n/sec/g PuO2 is used. The neutron yield from (α,n) reactions with oxygen is calculated by integrating the reaction rate equation over all alpha-particle energies and all centerofmass angles. The results indicate a neutron emission rate of (1.14 ± 0.26) × 104 n/sec/g PuO2. The neutron yield from (α,n) reactions with low Z impurities in the fuel is presented in tabular form for 1 ppm of each impurity. The total neutron yield due to the combined effects of all the impurities depends on the fractional weight concentration of each impurity. The total neutron flux emitted from a particular fuel geometry is estimated by adding the neutron yield due to the induced fission to the other neutron sources.
