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.
Explore membership for yourself or for your organization.
Conference Spotlight
2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
Latest Magazine Issues
Aug 2026
Jan 2026
2026
Latest Journal Issues
Nuclear Science and Engineering
October 2026
Nuclear Technology
September 2026
Fusion Science and Technology
August 2026
Latest News
Second round of Launch Pad selections includes eight newcomers
The National Reactor Innovation Center at Idaho National Laboratory has announced 13 project selections across 12 companies for the Nuclear Energy Launch Pad, a Department of Energy–led program that integrates reactor and fuel facility authorization, testing, and deployment support for private nuclear developers.
The Launch Pad emerged from the Reactor Pilot Program and Fuel Line Pilot Program.
According to INL, projects selected include reactor development and nuclear fuel cycle advancements, including fabrication, enrichment, and conversion technologies.
L. M. Gomes, P. N. Stevens
Fusion Science and Technology | Volume 19 | Number 3 | May 1991 | Pages 1996-2000
Neutronic | Proceedings of the Ninth Topical Meeting on the Technology of Fusion Energy (Oak Brook, Illinois, October 7-11, 1990) | doi.org/10.13182/FST91-A29634
Articles are hosted by Taylor and Francis Online.
This work revisits the problem of ray effects in discrete ordinates calculations that frequently occurs in two- and three-dimensional systems which contain isolated sources within a highly absorbing medium. The effectiveness of using a first collision source or a second collision source are analyzed as possible remedies to mitigate this problem. The first and second scattering sources are calculated with the Monte Carlo method that is intrinsically free from ray effects. The scattering source is then coupled to a discrete ordinates code for a hopefully ray-effect-free transport calculation. The scattering source generated by the Monte Carlo method is distributed throughout geometry space and therefore would be less likely to produce ray effects in the discrete ordinates calculation. This remedy for the ray effect is demonstrated for a point source in cylindrical geometry and for a localized distributed source in X-Y geometry. The first collision and second collision sources are generated by three-dimensional Monte Carlo calculations and enables its application to a variety of source configurations and the results can be coupled to a two- or three-dimensional discrete ordinates transport code. The Monte Carlo computational time and precision requirements constitute some limitations but these are minimized since the Monte Carlo transport is performed only up to the first collision.