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
Jul 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
August 2025
Nuclear Technology
Fusion Science and Technology
July 2025
Latest News
Hash Hashemian: Visionary leadership
As Dr. Hashem M. “Hash” Hashemian prepares to step into his term as President of the American Nuclear Society, he is clear that he wants to make the most of this unique moment.
A groundswell in public approval of nuclear is finding a home in growing governmental support that is backed by a tailwind of technological innovation. “Now is a good time to be in nuclear,” Hashemian said, as he explained the criticality of this moment and what he hoped to accomplish as president.
W. L. Whittemore
Nuclear Science and Engineering | Volume 24 | Number 4 | April 1966 | Pages 394-409
Technical Paper | doi.org/10.13182/NSE66-A16410
Articles are hosted by Taylor and Francis Online.
The General Atomic neutron velocity selector has been used in conjunction with the electron Linac to produce monoenergetic neutrons in the range 0.167 to 0.499 eV. The scattering of neutrons at various angles between 30 and 150° by a thin specimen of crystalline polyethylene has been measured, and precise scattering cross sections σ(E0, E, θ) have been determined. The experimental results are compared in detail with the theoretical work of Goldman, Parks, Koppel and Young, and McMurry. The detailed comparisons indicate that a more-or-less continuous realistic frequency distribution, or an appropriate collection of isolated oscillator levels, can be used as the basis of computing a reasonably satisfactory scattering cross section for polyethylene. It appears that the models of Goldman, Parks, and Koppel and Young all overemphasize energy transfers at ≈ 0.089 eV, and tend to underemphasize the largest transfers at ≈ 0.35 eV. The extrapolation technique of Egelstaff applied to the Scattering Law gives a frequency distribution that is similar in broad outline to that used by Parks. However, small significance can be attributed to this agreement because of the probable and large contributions of the multiphonon terms.