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Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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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
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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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Argonne’s METL gears up to test more sodium fast reactor components
Argonne National Laboratory has successfully swapped out an aging cold trap in the sodium test loop called METL (Mechanisms Engineering Test Loop), the Department of Energy announced April 23. The upgrade is the first of its kind in the United States in more than 30 years, according to the DOE, and will help test components and operations for the sodium-cooled fast reactors being developed now.
J. T. Mihalczo
Nuclear Science and Engineering | Volume 53 | Number 4 | April 1974 | Pages 393-414
Technical Paper | doi.org/10.13182/NSE74-5
Articles are hosted by Taylor and Francis Online.
Cross-correlation measurements between the pulses from an ionization counter containing a 252Cf neutron source, which provided the initiators of fission chains in a neutron-multiplying assembly, and the pulses from a detector observing the particles from the fission chains leaking from the assembly were performed for unmoderated and polyethylene-moderated uranium (∼93 wt% 235U)-metal cylindrical assemblies with uranium masses varying from 12 to 160 kg and with prompt-neu-tron decay constants varying from 3 × 103 to 108 sec-1. The applicability of this randomly pulsed neutron method with 252Cf as the neutron source for the determination of the prompt-neutron decay in plutonium was investigated in experiments with unmoderated plutonium-metal assemblies with masses varying from 2.2 to 16 kg and with spontaneous fission rates from 240Pu varying from 4.5 × 104 to 8.2 × 105 fiss/sec. These assemblies included spheres and parts of spheres of plutonium with 4.5 or 20.1 at.% 240Pu. The ratio of the correlated count rate in the randomly pulsed neutron method to that in a Rossi-α method is inversely proportional to the detector efficiency and was as large as 8000 for some assemblies where both measurements were made. Thus, the randomly pulsed neutron method allowed the determination of the prompt-neutron decay without the use of a complicated pulsed-neutron source where the Rossi-α method was not practical. In assemblies for which Rossi-α measurements were also made, the prompt-neutron decay constant agreed within the precision (<1%) of the measurements with those obtained in much less time by this technique. Since the prompt-neutron decay can also be determined for plutonium-metal assemblies with ∼20 at.% 240Pu, using a californium source as small as 3000 fiss/sec, this technique can be used for the subcriticality determination for both unreflected and unmoderated uranium (93.2)- or plutonium-metal assemblies.
