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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.
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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
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.
O. Petit, E. Dumonteil
Nuclear Technology | Volume 192 | Number 3 | December 2015 | Pages 259-263
Technical Paper | Radiation Transport and Protection | doi.org/10.13182/NT14-128
Articles are hosted by Taylor and Francis Online.
Monte Carlo simulations of nuclear instrumentation configurations generally need to be run in a full analog transport mode. Up to Version 9 of the Monte Carlo code TRIPOLI-4®, the transport between two consecutive neutron collisions is analog if no variance reduction technique is requested by the user, but the collision itself is sampled in a nonanalog way. This paper presents the first implementation of a full analog neutron transport mode in TRIPOLI-4. This option concerns only fixed-source simulations.
Details on the modifications implemented in the code are provided: The analog sampling of neutron interactions and the particular cases of fission and scattering reactions with multiple outgoing neutrons are addressed.
Preliminary verification tests are provided, and results from nonanalog and analog neutron transport in a simple configuration of a pressurized water reactor fuel assembly are compared. An example of application to the simulation of the NUCIFER detector is also provided. This experiment, located in Saclay, France, next to the OSIRIS experimental reactor, is dedicated to reactor antineutrino detection, addressing both nonproliferation considerations and fundamental physics concerns. Antineutrinos emitted by fission reactions in OSIRIS are detected through the inverse beta decay reaction, producing a positron and a neutron. An analog TRIPOLI-4 simulation allowed us to calculate the distribution of neutron capture times on gadolinium nuclei.
