Study on target structure for direct–indirect hybrid implosion mode in heavy ion inertial fusion

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 2009-07, Vol.606 (1), p.165-168
• Main Authors: Iizuka, Yoshifumi, Kawata, Shigeo, Kodera, Tomohiro, Ogoyski, Alexander I., Kikuchi, Takashi
• Format: Article
• Language: English
• Subjects: Direct–indirect hybrid implosion; Heavy ion beam; Inertial confinement fusion
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/j.nima.2009.03.090

The key issues in heavy ion beam (HIB) inertial confinement fusion (ICF) include particle accelerator, physics of intense beam, beam final transport, target-plasma hydrodynamics, etc. In this paper, we focus on fuel implosion. In order to realize an effective implosion, beam illumination non-uniformity on a fuel target must be suppressed less than a few percent. In this study a direct–indirect hybrid implosion mode is discussed in heavy ion beam inertial confinement fusion (HIF) in order to release sufficient fusion energy in a robust manner. In the direct–indirect hybrid mode target, a low-density foam layer is inserted, and the radiation energy is confined in the foam layer. In the foam layer, the radiation transport is expected to smoothen the HIB illumination non-uniformity in the lateral direction. In this paper, we study the influences of the foam thickness and the inner radiation-shield Al density on implosion uniformity. Two-dimensional fluid simulations demonstrate that the hybrid target contributes to the HIB non-uniformity smoothing and releases a sufficient fusion energy output in HIF.