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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Penn State and Westinghouse make eVinci microreactor plan official
Penn State and Westinghouse Electric Company are working together to site a new research reactor on Penn State’s University Park, Pa., campus: Westinghouse’s eVinci, a HALEU TRISO-fueled sodium heat-pipe reactor. Penn State has announced that it submitted a letter of intent to host and operate an eVinci reactor to the Nuclear Regulatory Commission on February 28 and plans to engage with the NRC on specific siting decisions. Penn State already boasts the Breazeale reactor, which began operating in 1955 as the first licensed research reactor at a university in the United States. At 70, the Breazeale reactor is still in operation.
Marshall F. Crouch
Nuclear Science and Engineering | Volume 2 | Number 5 | September 1957 | Pages 631-639
Technical Paper | doi.org/10.13182/NSE57-A25430
Articles are hosted by Taylor and Francis Online.
Fast neutrons are produced inside a water moderator by a Po-α-Be source used effectively as a pulsed neutron source. The slowing-down time to the Cd edge is measured with a BF3 proportional counter used with a cadmium difference technique. The mean slowing down time to O.35 ev, and the variance thereof, are found to be 5.2 µsec and 8.0 µsec2, respectively. It is shown that this is in reasonable agreement with the results of a Monte Carlo calculation, provided collisions are considered to involve whole H2O molecules when the neutron energy falls below about 1.6 ev.
