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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
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
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
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
W. M. Lopez, J. R. Beyster
Nuclear Science and Engineering | Volume 12 | Number 2 | February 1962 | Pages 190-202
Technical Paper | doi.org/10.13182/NSE62-A26058
Articles are hosted by Taylor and Francis Online.
Neutron diffusion parameters in water have been measured at 26.7°C with the pulsed neutron technique. The results are 210 ± 1 µsec for the neutron mean lifetime, 37,503 ± 366 cm2 sec−1 for the average diffusion coefficient, and 5116 ± 776 cm4 sec−1 for the diffusion cooling constant. From these values the thermal absorption cross section of hydrogen and the thermal diffusion length in water can be inferred to be 325 ± 2 mb and 2.83 ± 0.02 cm, respectively. With a pulsed high-intensity neutron source provided by an electron linear accelerator, neutron lifetime measurements were performed on small and large water samples with values of the geometrical buckling from 0.014 cm−2 to 0.59 cm−2. Effects of harmonic modes in the large water geometries, which were determined by measurements of the time-dependent spatial flux distributions resulting from an external pulsed source of fast neutrons, were found to be adequately predictable with simple diffusion theory.
