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 ANS Annual Conference
May 31–June 3, 2026
Denver, CO|Sheraton Denver
Latest Magazine Issues
Feb 2026
Jul 2025
Latest Journal Issues
Nuclear Science and Engineering
March 2026
Nuclear Technology
February 2026
Fusion Science and Technology
January 2026
Latest News
Fusion energy: Progress, partnerships, and the path to deployment
Over the past decade, fusion energy has moved decisively from scientific aspiration toward a credible pathway to a new energy technology. Thanks to long-term federal support, we have significantly advanced our fundamental understanding of plasma physics—the behavior of the superheated gases at the heart of fusion devices. This knowledge will enable the creation and control of fusion fuel under conditions required for future power plants. Our progress is exemplified by breakthroughs at the National Ignition Facility and the Joint European Torus.
Birchard L. Kortegaard
Fusion Science and Technology | Volume 11 | Number 3 | May 1987 | Pages 671-683
Technical Paper | KrF Laser | doi.org/10.13182/FST87-A25042
Articles are hosted by Taylor and Francis Online.
A control system is described that aligns the 96 beams of the Los Alamos National Laboratory KrF laser system to within a pointing accuracy of 5 µrad within 5 min and maintains the alignment in real time. This performance is made possible through a novel use of random noise. The 96 beams, together with optical benchmarks, are imaged on a single television (TV) camera. The pointing angles of those beams are estimated from the arithmetic means of the pixel coordinates within the beam images. The pixel intensities of each TV frame are mapped into a binary decision array based on whether or not the pixel intensity is above or below a threshold criterion. Existing, or introduced, random noise in the TV signal causes the contents of this array to vary from frame to frame, even when the actual beam is stationary. The beam positions are estimated from the pixel coordinates and their associated elements within this array. Finally, the beam angle estimates are updated from these position estimates, each TV frame, in combination with all previous estimates. This finds the contributions of the beam edges to the beam position by directly using pixels with intensities both above and below the beam threshold criteria, eliminating the need (possibly unrealizable) to do so by software interpolation algorithms. It does this very quickly, resulting in great data compression without use of computer time.