Gamma-ray measurements for inertial confinement fusion applications

High-energy. rays generated from inertial confinement fusion (ICF) experiments have become an important signature for studying the dynamics of implosion processes. Due to their high-energy and penetrating nature, gamma rays are the most unperturbed fusion products, which can preserve the original birth information of the fusion process. Fusion. rays provide a direct measure of nuclear reaction rates (unlike x rays) without being compromised by Doppler spreading (unlike neutrons). However, unambiguous gamma-ray measurements for ICF study further required a decade-long period of technological development, which included a deepening understanding of fusion gamma-ray characteristics and innovations in instrument performance. This review article introduces the production mechanism of the prompt and secondary. rays and various ICF performance parameters (e.g., bang time and burn width), which can be derived from gamma-ray measurement. A technical overview will be followed by summarizing gamma-ray detectors fielded or proposed, especially for high-yield ICF experiments at the Omega Laser Facility and National Ignition Facility. Over the past few years, gamma-ray diagnostic technologies have been extended beyond ICF research. A few examples of non-ICF applications of gamma-ray detectors are introduced at the end of this article. (c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).