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Division Spotlight
Operations & Power
Members focus on the dissemination of knowledge and information in the area of power reactors with particular application to the production of electric power and process heat. The division sponsors meetings on the coverage of applied nuclear science and engineering as related to power plants, non-power reactors, and other nuclear facilities. It encourages and assists with the dissemination of knowledge pertinent to the safe and efficient operation of nuclear facilities through professional staff development, information exchange, and supporting the generation of viable solutions to current issues.
Meeting Spotlight
ANS Student Conference 2025
April 3–5, 2025
Albuquerque, NM|The University of New Mexico
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
Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
Renato Yoichi Ribeiro Kuramoto, Adimir dos Santos, Rogario Jerez, Ricardo Diniz
Nuclear Science and Engineering | Volume 158 | Number 3 | March 2008 | Pages 272-283
Technical Paper | doi.org/10.13182/NSE06-120
Articles are hosted by Taylor and Francis Online.
A new method for absolute measurement of the effective delayed neutron fraction eff based on Rossi- experiments and the two-region model was developed at the IPEN/MB-01 Research Reactor facility. In contrast with other techniques such as the slope method, the Nelson-number method, and the 252Cf-source method, the main advantage of this new methodology is to obtain the effective delayed neutron parameters in a purely experimental way, eliminating all parameters that are difficult to measure or calculate. In this way, Rossi- experiments for validation of this method were performed at the IPEN/MB-01 facility, and with the use of the present approach, eff was measured with a 1.46% uncertainty. In addition, the prompt neutron generation time and other parameters were also obtained in an absolute experimental way. In general, the final results agree well with values from frequency analysis experiments. Comparison of theory and experiment reveals that JENDL-3.3 shows deviation for eff lower than 1%, which meets the desired accuracy for the theoretical determination of this parameter. This work supports the reduction of the 235U thermal yield, as proposed by Okajima and Sakurai.