ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
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
El Salvador: Looking to nuclear
In 2022, El Salvador’s leadership decided to expand its modest, mostly hydro- and geothermal-based electricity system, which is supported by expensive imported natural gas and diesel generation. They chose to use advanced nuclear reactors, preferably fueled by thorium-based fuels, to power their civilian efforts. The choice of thorium was made to inform the world that the reactor program was for civilian purposes only, and so they chose a fuel that was plentiful, easy to source and work with, and not a proliferation risk.
M. R. Hartman, S. T. Keller, S. R. Reese, B. Robinson, J. Stevens, J. E. Matos, W. R. Marcum, T. S. Palmer, B. G. Woods
Nuclear Science and Engineering | Volume 174 | Number 2 | June 2013 | Pages 135-149
Technical Paper | doi.org/10.13182/NSE12-5
Articles are hosted by Taylor and Francis Online.
In support of the conversion of the Oregon State TRIGA Reactor (OSTR) from highly enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel, a comprehensive neutronic analysis utilizing MCNP5 was performed on the HEU and LEU core configurations. The initial 1974 HEU core provided an opportunity for verification of the MCNP5 baseline model; all fuel elements in the initial core were congruent in geometry and material composition, having no burnup. In addition, a substantial database of core parameters was documented during the initial HEU core start-up. This verification study examined control rod worth, core excess reactivity, burnup, core power, power per element, temperature coefficient of reactivity, void coefficient of reactivity, moderator coefficient of reactivity, axial and radial power profiles, prompt-neutron lifetime, effective delayed-neutron fraction, power defect, and xenon poisoning.Fuel material composition and core loadings are presented. The excellent comparison between the numerical results and the experimental data of the initial HEU core established an objective, credible baseline model and methodology, which were then extended to the LEU core neutronic analysis. Comparison between the numerically calculated core physics values for the new LEU core and data collected during start-up provided a complete verification that the MCNP5 models developed for both the HEU and LEU cores were representative of the OSTR.
