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Division Spotlight
Reactor Physics
The division's objectives are to promote the advancement of knowledge and understanding of the fundamental physical phenomena characterizing nuclear reactors and other nuclear systems. The division encourages research and disseminates information through meetings and publications. Areas of technical interest include nuclear data, particle interactions and transport, reactor and nuclear systems analysis, methods, design, validation and operating experience and standards. The Wigner Award heads the awards program.
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
Lightbridge announces first U-Zr fuel rod samples extruded at INL
Lightbridge Corporation announced today that it has reached “a critical milestone” in the development of its extruded solid fuel technology. Coupon samples using an alloy of zirconium and depleted uranium—not the high-assay low-enriched uranium (HALEU) that Lightbridge plans to use to manufacture its fuel for the commercial market—were extruded at Idaho National Laboratory’s Materials and Fuels Complex.
B. Becker, A. Weltz, J. A. Kulisek, J. Thompson, N. Thompson, Y. Danon
Nuclear Science and Engineering | Volume 175 | Number 2 | October 2013 | Pages 124-134
Technical Paper | doi.org/10.13182/NSE12-66
Articles are hosted by Taylor and Francis Online.
The use of a lead slowing-down spectrometer (LSDS) is considered as a possible option for nondestructive assay of fissile material of used nuclear fuel. The primary objective is to quantify fissile isotopes, particularly 239Pu and 235U, via a direct measurement distinguishing them through their characteristic fission spectra in the LSDS. In this paper, we present several assay measurements performed at the Rensselaer Polytechnic Institute (RPI) to support ongoing feasibility studies of the method and to provide benchmark experiments for Monte Carlo calculations of the assay system. A fresh uranium oxide fuel rod from the RPI Walthousen Reactor Critical Facility, a 239Pu-Be source, and several highly enriched 235U disks were assayed in the LSDS. The characteristic fission spectra were measured with 238U and 232Th threshold fission chambers, which are primarily sensitive to fission neutrons with energies above the threshold. Despite the constant neutron and gamma background from the Pu-Be source and the intense interrogation neutron flux, the LSDS system was able to measure the characteristic 235U and 239Pu responses. All measurements were compared to Monte Carlo simulations complementing previous modeling-based studies. It is shown that the available simulation tools and models are well suited to simulate the assay. An absolute calibration technique of the LSDS, which is required to perform quantitative measurements of the assayed fissile materials, is presented.