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Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
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2024 ANS Winter Conference and Expo
November 17–21, 2024
Orlando, FL|Renaissance Orlando at SeaWorld
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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New laws offer nuclear industry incentives for existing power plant uprates
This year, the U.S. nuclear industry received a much-needed economic boost that could help preserve operating nuclear power plants and incentivize upgrades that extend their lifespan and power output.
Signed into law in 2022, the Inflation Reduction Act offers production tax credits (PTCs) for existing nuclear power plants and either PTCs or investment tax credits (ITCs) for new carbon-free generation. These credits could make power uprates—increasing the maximum power level at which a commercial plant may operate—a much more appealing option for utilities.
V. V. Verbinski, J. C. Young, J. M. Neill
Nuclear Science and Engineering | Volume 52 | Number 3 | November 1973 | Pages 330-342
Technical Paper | doi.org/10.13182/NSE73-A19480
Articles are hosted by Taylor and Francis Online.
Cylindrical proportional counters were used to measure the scalar neutron flux in the core and reflector of the 235U-fueled fast subcritical reactors, STSF-7 and -9. These data have been compared with time-of-flight angular spectrum measurements in the same reactors, and with transport theory calculations of these assemblies utilizing ENDF/B-III cross sections. The agreement of the two measurement techniques at high energy indicates that the emission time correction procedures used for the time-of-flight studies on subcritical (keff = ≈0.92) assemblies with a 220-m flight path are reliable. At intermediate energies, the two types of measurements and the calculations were in good agreement for the STSF-9 oxide-fueled core, but significantly different for the metal-fueled STSF-7 core in the region of fine structure associated with the pronounced aluminum resonances below 300 keV. The time-of-flight data exhibited some energy mismatch here, and the 4π counter was subjected to more aluminum “shielding” than allowed for in the calculations. The shielding effect was strongest in the metal-fueled STSF-7 core, because of the absence of the oxygen moderator. At low energy, where the Doppler effects of the thermal coefficient of reactivity are concentrated, the calculations underpredict the flux. The time-of-flight data, which are the most reliable here, show the greatest disagreement with theory.