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
Nuclear Energy Conference & Expo (NECX)
September 8–11, 2025
Atlanta, GA|Atlanta Marriott Marquis
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
Latest Magazine Issues
Aug 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
September 2025
Nuclear Technology
Fusion Science and Technology
August 2025
Latest News
Powering the future: How the DOE is fueling nuclear fuel cycle research and development
As global interest in nuclear energy surges, the United States must remain at the forefront of research and development to ensure national energy security, advance nuclear technologies, and promote international cooperation on safety and nonproliferation. A crucial step in achieving this is analyzing how funding and resources are allocated to better understand how to direct future research and development. The Department of Energy has spearheaded this effort by funding hundreds of research projects across the country through the Nuclear Energy University Program (NEUP). This initiative has empowered dozens of universities to collaborate toward a nuclear-friendly future.
Felix C. Difilippo
Nuclear Science and Engineering | Volume 104 | Number 2 | February 1990 | Pages 123-134
Technical Paper | doi.org/10.13182/NSE90-A23709
Articles are hosted by Taylor and Francis Online.
The harmonic expansion of the detector field of view in terms of direct and adjoint kinetic eigenfunctions together with the use of a modified version of the Schottky prescription of the equivalent source of noise make possible the harmonic analysis of stochastic descriptors used in the measurement of kinetic parameters. The results are general in the sense that they do not depend on the approximations of the Boltzmann operator, the distribution of fissile materials, or the multiplicity of the neutron source that drives the subcritical system. The results are applied to analyze the particular case of a system driven by a 252Cf source, with the californium deposited in one of the electrodes of a fission chamber and monitored by two sets of neutron detectors. This analysis is oriented toward the interpretation of experiments to measure reactivities with the stochastic method of the 252Cf source (ratio method). The theory is then used to synthesize stochastic observables using a simple approximation of the Boltzmann operator, i.e., two-point kinetics, which show the general features of the spatial effects observed experimentally.
