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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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A webinar, and a new opportunity to take ANS’s CNP Exam
Applications are now open for the fall 2025 testing period for the American Nuclear Society’s Certified Nuclear Professional (CNP) exam. Applications are being accepted through October 14, and only three testing sessions are offered per year, so it is important to apply soon. The test will be administered from November 12 through December 16. To check eligibility and schedule your exam, click here.
In addition, taking place tomorrow (September 19) from 12:00 noon to 1:00 p.m. (CDT), ANS will host a new webinar, “How to Become a Certified Nuclear Professional.” More information is available below in this article.
J. I. Katz
Nuclear Science and Engineering | Volume 168 | Number 2 | June 2011 | Pages 164-171
Technical Paper | doi.org/10.13182/NSE10-19
Articles are hosted by Taylor and Francis Online.
This paper reviews measurements of fission cross sections of short-lived nuclear states, summarizes the formidable experimental difficulties involved, and suggests novel methods of overcoming some of those difficulties. It is specifically concerned with the two such states that have been well characterized, the J = 1/2+ (26-min) isomeric 235mU and the J = 1- (16-h) ground state (shorter lived than the isomer) 242gsAm, and with measuring their fission cross sections at mega-electron-volt energies. These measurements are formidably difficult, partly because of the need to produce, separate, and collect the short-lived states before they decay and partly because of their comparatively small fission cross sections at these energies. This paper presents quantitative calculations of the efficiency of advection of recoiling 235mU isomers by flowing gas in competition with diffusive loss to the surface containing the mother 239Pu, and it reports the initial development and evaluation of some of the methods that must be developed to make the experiments feasible.