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
2025 ANS Winter Conference & Expo
November 8–12, 2025
Washington, DC|Washington Hilton
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
Oct 2025
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
November 2025
Nuclear Technology
Fusion Science and Technology
Latest News
Japan gets new U for enrichment as global power and fuel plans grow
President Trump is in Japan today, with a visit with new Prime Minister Sanae Takaichi on the agenda. Takaichi, who took office just last week as Japan’s first female prime minister, has already spoken in favor of nuclear energy and of accelerating the restart of Japan’s long-shuttered power reactors, as Reuters and others have reported. Much of the uranium to power those reactors will be enriched at Japan’s lone enrichment facility—part of Japan Nuclear Fuel Ltd.’s Rokkasho fuel complex—which accepted its first delivery of fresh uranium hexafluoride (UF₆) in 11 years earlier this month.
K. Ohkubo, S. Kubo, T. Shimozuma, Y. Yoshimura, H. Igami, S. Kobayashi
Fusion Science and Technology | Volume 62 | Number 3 | November 2012 | Pages 389-402
Technical Paper | doi.org/10.13182/FST12-A15338
Articles are hosted by Taylor and Francis Online.
In the system of electron cyclotron heating, highly overmoded, corrugated circular waveguides are used. To analyze propagating mode content in the waveguide, burn patterns of the thermal paper placed on the waveguide aperture are observed at several positions. Theoretical burn patterns are obtained by taking into account a nonlinear grayscale response of the thermal paper to the calculated power profiles. We have developed a new method of mode analysis by nonlinear optimization, which is based on an iterative error reduction of differences between observed and theoretical patterns. To examine the status of polarization, the transformation between hybrid modes and linearly polarized (LP) modes is derived. The method is applied to the 82.7-GHz transmission line connected with the gyrotron. The propagating wave is linear polarized and consists of [approximately]4% of the LP11 odd mode, [approximately]95% of the LP01 mode, and [approximately]1% of other modes. The calculated burn pattern is similar to the observed one, like a plateau. By using both center of power and weighted averages of the perpendicular wavenumber in these profiles, offset and tilting angles of an injecting electromagnetic beam to the waveguide entrance are inferred. These are verified to be consistent with the results by the coupling code of a Gaussian beam with hybrid modes.
