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.
C. Budtz-Jørgensen, H.-H. Knitter
Nuclear Science and Engineering | Volume 86 | Number 1 | January 1984 | Pages 10-21
Technical Paper | doi.org/10.13182/NSE84-A17966
Articles are hosted by Taylor and Francis Online.
An ionization chamber with a Frisch grid is used to determine both the energy (E) of the charged particles emitted from the source positioned coplanar with the cathode, and the cosine of the emission angle (ϑ) with respect to the normal of the cathode. In the plane determined by the variables cosϑ and E, it is possible to identify an area that is unaffected by backscattering and self-absorption. Events belonging to this area show an isotropic angular distribution for alpha particles and also for fragments of fission induced by thermal neutrons, which, extrapolated to 90 deg, yields the absolute number of events. The capabilities of this technique are demonstrated by the investigation of four evaporated 235UF4 layers and one suspension-sprayed 235U3O8 layer. For the UF4 layers, the alpha-particle source strengths were determined, and agreement was found within 0.3% with values independently measured by low-geometry alpha counting. The same method was also applied to fission events induced by thermal neutrons. The determination of the total number of fission events is determined to an accuracy of better than 0.5%. The longstanding doubts on the magnitudes of fragment absorption and scattering are, in principle, circumvented by the present method, and therefore no assumptions on fragment ranges and scattering cross sections are needed. It is emphasized that the present method, within reasonable limits, is insensitive to source shape and homogeneity in its thickness.