Experimentally Inferred Fusion Yield Dependencies of OMEGA Inertial Confinement Fusion Implosions
A Lees1,2, R Betti1,2,3, J P Knauer1
1Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
Physical Review Letters
|September 17, 2021
Summary
Statistical modeling accurately predicts fusion yield in OMEGA laser cryogenic implosions. Key factors degrading yield include laser-target ratio, ion temperature asymmetry, and tritium decay.
Area of Science:
- Nuclear Fusion Science
- Plasma Physics
- Laser-Inertial Confinement Fusion
Background:
- Accurate predictive models are crucial for inertial confinement fusion (ICF) research.
- Cryogenic implosions at the OMEGA laser facility generate significant fusion yields.
Purpose of the Study:
- To develop a physics-based statistical mapping framework for predicting fusion yield.
- To identify and quantify mechanisms that degrade fusion yield in direct-drive implosions.
Main Methods:
- Statistical modeling of experimental and simulation databases.
- Development of a physics-based statistical mapping framework.
- Analysis of dependencies between implosion parameters and fusion yield.
Main Results:
- Fusion yield is reduced by laser-target radius ratio, ion temperature asymmetry (ℓ=1 mode), tritium fuel decay time, and hydrodynamic stability parameters.
- The model quantifies specific degradation mechanisms affecting fusion performance.
- Adjusted for key factors, OMEGA implosions are predicted to exceed 2×10^14 fusion reactions.
Conclusions:
- Statistical modeling provides accurate predictive capabilities for cryogenic implosions.
- Understanding degradation mechanisms is key to optimizing fusion yield.
- High fusion yields are achievable with improved control over implosion parameters.
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