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.
Division Spotlight
Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
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
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
June 2025
Nuclear Technology
Fusion Science and Technology
May 2025
Latest News
Ariz. governor vetoes “fast track” bill for nuclear
Gov. Katie Hobbs put the brakes on legislation that would have eliminated some of Arizona’s regulations and oversight of small modular reactors, technology that is largely under consideration by data centers and heavy industrial power users.
Shin-ichi Ito
Nuclear Science and Engineering | Volume 49 | Number 4 | December 1972 | Pages 458-467
Technical Paper | doi.org/10.13182/NSE72-A22565
Articles are hosted by Taylor and Francis Online.
A new method is presented for investigating the behavior of pulsed fast neutrons in non-multiplying semi-infinite systems. The time- and space-dependent multigroup P1 equation (of the telegrapher’s equation type) was analytically solved by the use of the Laplace transform. Starting from the space dependent first time moments on the decaying group-wise neutron fluxes, the propagation parameters are newly defined as the fundamental parameters to describe the characteristics of the fast neutron moderation in the medium. These parameters include the space independent mean life time and the inverse of the effective velocity of neutron propagation. The proposed method will be useful in investigating the space dependent neutron slowing down and propagation phenomena in assemblies.