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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!
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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.
E.A. Straker
Nuclear Science and Engineering | Volume 46 | Number 3 | December 1971 | Pages 334-355
Technical Paper | doi.org/10.13182/NSE71-A22371
Articles are hosted by Taylor and Francis Online.
Calculations have been made of the space, energy, angle, and time dependence of the neutron and secondary gamma-ray fields produced in the atmosphere by several neutron sources, and the results for a 12.2- to 15-MeV source and a fission source are compared in this paper. They include steady-state and time-dependent results at ranges out to 1500 m for both an infinite air medium and an air-over-ground medium, the latter for source heights of 15 and 343 m. The data show that the neutron doses and dose rates from the 12.2- to 15-MeV source are higher than those from the fission source in all geometries and time intervals. While the secondary gamma-ray doses produced by the 12.2- to 15-MeV source also are higher than those produced by the fission source in all geometries, the secondary dose rates are higher only for times less than 10-3 sec, after which the dose rates from the two sources are comparable. The effects of the ground are to enhance both the neutrons and the secondary gamma rays at ranges close to the source and to act as an absorber at ranges far from the source. These effects decrease with increasing source height.
