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.
Isotopes & Radiation
Members are devoted to applying nuclear science and engineering technologies involving isotopes, radiation applications, and associated equipment in scientific research, development, and industrial processes. Their interests lie primarily in education, industrial uses, biology, medicine, and health physics. Division committees include Analytical Applications of Isotopes and Radiation, Biology and Medicine, Radiation Applications, Radiation Sources and Detection, and Thermal Power Sources.
Nuclear and Emerging Technologies for Space (NETS 2023)
May 7–11, 2023
Idaho Falls, ID|Snake River Event Center
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
Latest Journal Issues
Nuclear Science and Engineering
Fusion Science and Technology
The blossoming of cooperation between the U.S. and Canada
The United States and Canadian nuclear industries used to be an example of how two independent teams of engineers facing an identical problem—making electricity from uranium—could come up with completely different answers. In the 1950s, Canada began designing a reactor with tubes, heavy water, and natural uranium, while in the U.S. it was big pots of light water and enriched uranium.
But 80 years later, there is a remarkable convergence. The North American push for a new generation of nuclear reactors, mostly small modular reactors (SMRs), is becoming binational, with U.S. and Canadian companies seeking markets and regulatory certification on both sides of the border and in many cases sourcing key components in the other country.
Tuomas Viitanen, Jaakko Leppänen
Nuclear Science and Engineering | Volume 177 | Number 1 | May 2014 | Pages 77-89
Technical Paper | doi.org/10.13182/NSE13-37
Articles are hosted by Taylor and Francis Online.
The target motion sampling (TMS) temperature treatment technique, previously known as “explicit treatment of target motion,” is a stochastic method for taking the effect of thermal motion on reaction rates into account on-the-fly during Monte Carlo neutron tracking. The method is based on sampling target velocities at each collision site and dealing with the collisions in the target-at-rest frame using cross sections below the actual temperature of the nuclide or, originally, 0 K. Previous results have shown that transport with the original implementation of the TMS method requires about two to four times more CPU time than conventional transport methods, depending on the case. In the present paper, it is observed that the overhead factor may increase even above 10 in cases involving burned fuel. To make the method more practical for everyday use, some optimization is required. This paper discusses a TMS optimization technique in which the temperatures of the basis cross sections are elevated above 0 K. Comparisons show that the TMS method is able to reproduce the NJOY-based reference results within statistical accuracy, both with and without the newly implemented optimization technique. In the specific test cases, the optimization saved 35% to 83% of the calculation time, depending on the case.