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
August 2025
Fusion Science and Technology
Latest News
Chris Wagner: The role of Eden Radioisotopes in the future of nuclear medicine
Chris Wagner has more than 40 years of experience in nuclear medicine, beginning as a clinical practitioner before moving into leadership roles at companies like Mallinckrodt (now Curium) and Nordion. His knowledge of both the clinical and the manufacturing sides of nuclear medicine laid the groundwork for helping to found Eden Radioisotopes, a start-up venture that intends to make diagnostic and therapeutic raw material medical isotopes like molybdenum-99 and lutetium-177.
R. M. Bansal, S. P. Tewari
Nuclear Science and Engineering | Volume 65 | Number 2 | February 1978 | Pages 419-422
Technical Note | doi.org/10.13182/NSE78-A27171
Articles are hosted by Taylor and Francis Online.
The pulsed neutron problem is studied in small but finite sized assemblies of liquid water and heavy water poisoned with such non-1/v neutron absorbers as samarium, cadmium, and gadolinium. It is found that the asymptotic neutron density is markedly dependent on the nature of the non-1/v absorber. For a given buckling, one can find a critical concentration of gadolinium that will give a Maxwellian asymptotic neutron distribution. Thus, a finite assembly in the presence of a definite concentration of gadolinium acts as an infinite assembly. This is not the case with samarium or cadmium.