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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.
G. Leinweber, J. A. Burke, H. D. Knox, N. J. Drindak, D. W. Mesh, W. T. Haines, R. V. Ballad, R. C. Block, R. E. Slovacek, C. J. Werner, M. J. Trbovich, D. P. Barry, T. Sato
Nuclear Science and Engineering | Volume 142 | Number 1 | September 2002 | Pages 1-21
Technical Paper | doi.org/10.13182/NSE02-A2283
Articles are hosted by Taylor and Francis Online.
The purpose of the present work is to measure the neutron cross sections of samarium accurately. The most significant isotope is 149Sm, which has a large neutron absorption cross section at thermal energies and is a 235U fission product with a 1% yield. Its cross sections are thus of concern to reactor neutronics.Neutron capture and transmission measurements were performed by the time-of-flight technique at the Rensselaer Polytechnic Institute (RPI) LINAC facility using metallic and liquid Sm samples. The capture measurements were made at the 25-m flight station with a multiplicity-type capture detector, and the transmission total cross-section measurements were performed at 15- and 25-m flight stations with 6Li glass scintillation detectors. Resonance parameters were determined by a combined analysis of six experiments (three capture and three transmission) using the multilevel R-matrix Bayesian code SAMMY version M2.The significant features of this work are as follows. Dilute samples of samarium nitrate in deuterated water (D2O) were prepared to measure the strong resonances at 0.1 and 8 eV without saturation. Disk-shaped spectroscopic quartz cells were obtained with parallel inner surfaces to provide a uniform thickness of solution. The diluent feature of the SAMMY program was used to analyze these data. The SAMMY program also includes multiple-scattering corrections to capture yield data and resolution functions specific to the RPI facility.Resonance parameters for all stable isotopes of samarium were deduced for all resonances up to 30 eV. Thermal capture cross-section and capture resonance integral (RI) calculations were made using the resultant resonance parameters and were compared to results obtained using resonance parameters from ENDF/B-VI updated through release 3. Extending the definition of the capture RI to include the strong 0.1-eV resonance in 149Sm, present measurements agree within estimated uncertainties with ENDF/B-VI release 3. The thermal capture cross section was calculated from the present measurements of the resonance parameters and also agrees with ENDF within estimated uncertainties. The present measurements reduce the statistical uncertainties in resonance parameters compared to prior measurements.
