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Young Members Group
The Young Members Group works to encourage and enable all young professional members to be actively involved in the efforts and endeavors of the Society at all levels (Professional Divisions, ANS Governance, Local Sections, etc.) as they transition from the role of a student to the role of a professional. It sponsors non-technical workshops and meetings that provide professional development and networking opportunities for young professionals, collaborates with other Divisions and Groups in developing technical and non-technical content for topical and national meetings, encourages its members to participate in the activities of the Groups and Divisions that are closely related to their professional interests as well as in their local sections, introduces young members to the rules and governance structure of the Society, and nominates young professionals for awards and leadership opportunities available to members.
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ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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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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Latest News
First astatine-labeled compound shipped in the U.S.
The Department of Energy’s National Isotope Development Center (NIDC) on March 31 announced the successful long-distance shipment in the United States of a biologically active compound labeled with the medical radioisotope astatine-211 (At-211). Because previous shipments have included only the “bare” isotope, the NIDC has described the development as “unleashing medical innovation.”
J. T. Mihalczo, E. D. Blakeman, V. K. Paré, T. E. Valentine, D. J. Auslander
Nuclear Technology | Volume 103 | Number 3 | September 1993 | Pages 346-379
Technical Paper | Nuclear Criticality Safety | doi.org/10.13182/NT93-3
Articles are hosted by Taylor and Francis Online.
The subcritical neutron multiplication factors k for two parallel, axially separated, flat cylindrical tanks separated up to 57.91 cm in air and containing enriched uranyl (93.1 wt% 235U) nitrate solution (71.6-cm-i.d. tanks, 8.91-cm solution thickness, 1.555 g/cm3 solution density, and 404 g U/ℓ uranium density) were measured by the 252Cf-source-driven noise analysis method with measured k values varying from 0.99 to 0.80. These measurements were performed at the Los Alamos National Laboratory (LANL) Critical Experiments Facility in 1989 and were part of the program of Westinghouse Idaho Nuclear Company (WINCO) to benchmark calculations for the design of the new storage system at Idaho National Engineering Laboratory. Initial subcriticality measurements by the source-jerk method at LANL had indicated that at a calculated neutron multiplication factor k = 0.95, the measured k was 0.975. This discrepancy was of concern to WINCO because the new storage facility was being designed with a k limit of 0.95, and thus, half of the criticality safety margin of the storage design was equal to the discrepancy between early measurements and calculations. The 252Cf-source-driven noise analysis measurements confirmed the validity of the calculational methods. In addition to providing the neutron multiplication factor from point-kinetics interpretation of the data, these measurements also provided the auto-power and crosspower spectral densities as a function of frequency, which can be calculated directly with recently developed Monte Carlo methods and thus could also be used to validate calculational methods and cross-section sets. As with previous measurements with loosely coupled systems, a modified point-kinetics interpretation was successfully used to obtain neutron multiplication factors for measurements with the californium source and detectors located on the same tank. Although the californium source is located on axis but asymmetrically in the system, the detectors adjacent to the radial surface were sufficiently far apart that the correlated information was from long fission chains, which are distributed throughout the system of two tanks. The subcritical neutron multiplication factors obtained from the break frequency noise analysis method agreed with those from the 252Cf-source-driven noise method. These measurements confirmed the criteria from previous experiments for location of the source and detectors to obtain the neutron multiplication factor by using a modified point-kinetics interpretation of the data and again verified the usefulness of this method for interacting systems.
