ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
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.
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!
Latest Magazine Issues
Apr 2025
Jan 2025
Latest Journal Issues
Nuclear Science and Engineering
May 2025
Nuclear Technology
April 2025
Fusion Science and Technology
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.
T. H. Trumbull, D. R. Harris
Nuclear Technology | Volume 154 | Number 1 | April 2006 | Pages 117-127
Technical Paper | Radiation Measurements and Instrumentation | doi.org/10.13182/NT06-A3722
Articles are hosted by Taylor and Francis Online.
Measurements of delayed fission product gamma-ray transmission through low-enriched UO2 fuel pin lattices in an air medium were conducted at the Rensselaer Polytechnic Institute Reactor Critical Facility (RCF). The RCF core consists of excess Special Power Excursion Reactor Test fuel pins enriched to 4.81 wt% 235U and clad in stainless steel. An experimental apparatus was constructed to hold various arrangements of fuel pin lattices. The arrangements consisted of a single activated source pin taken from the reactor core surrounded by inactive fuel pins in an air medium. A sodium-iodide detector and gamma-ray spectroscopy system was used to generate a pulse-height spectrum of the gamma-ray radiation for detector positions outside the lattice. The change in radiation intensity as the detector is rotated about the vertical axis of the lattice, the "channeling effect," was measured. Measurements of the channeling effect were performed for six experimental arrangements: 3 × 3, 5 × 5, and 7 × 7 lattices, with both the corner and the center positions containing the activated pin. The results of the measurements demonstrate that the gamma-ray radiation intensity can vary widely as a function of angle relative to the angle of rotation about the vertical axis of the lattice.