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arXiv · 1503.08979

Indirect-direct hybrid-drive work-dominated hotspot ignition for inertial confinement fusion

X. T. He·Z. F. Fan·J. W. Li·J. Liu·K. Lan·J. F. Wu·L. F. Wang·W. H. Ye
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Abstract

An indirect-direct hybrid-drive work-dominated hotspot ignition scheme for inertial confinement fusion is proposed: a layered fuel capsule inside a spherical hohlraum with an octahedral symmetry is compressed first by indirect-drive soft-x rays (radiation) and then by direct-drive lasers in last pulse duration. In this scheme, an enhanced shock and a follow-up compression wave for ignition with pressure far greater than the radiation ablation pressure are driven by the direct-drive lasers, and provide large pdV work to the hotspot to perform the work-dominated ignition. The numerical simulations show that the enhanced shock stops the reflections of indirect-drive shock at the main fuel-hotspot interface, and therefore significantly suppresses the hydrodynamic instabilities and asymmetry. Based on the indirect-drive implosion dynamics the hotspot is further compressed and heated by the enhanced shock and follow-up compression wave, resulting in the work-dominated hotspot ignition and burn with a maximal implosion velocity of ~400 km/s and a lower convergence ratio of ~25. The fusion yield of 15 MJ using total laser energy of 1.32 MJ is achieved.

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X. T. He, Z. F. Fan, J. W. Li, J. Liu, K. Lan, J. F. Wu, L. F. Wang, W. H. Ye. 2015-03-31. Indirect-direct hybrid-drive work-dominated hotspot ignition for inertial confinement fusion. https://arxiv.org/abs/1503.08979

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