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Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
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
DTE Energy studying uprate at Fermi-2, considers Fermi-3’s prospects
DTE Energy, the owner of Fermi nuclear power plant in Michigan, is considering an extended uprate for Unit 2 that would increase its 1,100-MW generation capacity by 150 MW.
E. Johansson, E. Jonsson
Nuclear Science and Engineering | Volume 25 | Number 2 | June 1966 | Pages 157-164
Technical Paper | doi.org/10.13182/NSE66-A17732
Articles are hosted by Taylor and Francis Online.
Using the fast chopper at the Stockholm reactor R1, we have measured angular neutron-flux spectra in an arrangement consisting of short uranium rods in heavy water. The rods were mounted in an aluminum container placed in the central vertical channel of the reactor. The axes of the rods were horizontal and approximately located in a vertical plane. The uranium was 29-mm diam, the aluminum can was 1-mm thick, and the spacing was about 140 mm. We measured (E,, in the vertical direction , for various positions . At 1 eV the results obtained were equal to each other within ±7%, but in the thermal region, they differed considerably. Thus, at 0.01 eV, the highest value measured was as much as 4.5 times the lowest one. In spite of the unclean geometry, we have also calculated the angular-flux spectra, starting from scalar-flux spectra obtained from the THERMOS code. The shape of the calculated spectra of the angular flux agreed within a few percent with the experimental spectra. From a combination of calculated and experimental results, we also obtained the spectrum of the incoming neutron current for a fuel rod. This current proved to have a neutron temperature about 7°C above the neutron temperature of the flux halfway between two rods. In the low-energy region (around 0.015 eV) the out-flux from a rod showed a wavy variation, believed to depend on Bragg effects in the metal.