Thermonuclear ignition and the onset of propagating burn in inertial fusion implosions
- Univ. of Rochester, NY (United States)
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Separating ignition of the central hot spot from propagating burn in the surrounding dense fuel is crucial to conclusively assess the achievement of ignition in inertial confinement fusion (ICF). We show that the transition from hot spot ignition to the onset of propagating burn occurs when the alpha heating within the hot spot has amplified the fusion yield by 15 to 25x with respect to the compression-only case without alpha energy deposition. This yield amplification corresponds to a value of the fractional alpha energy ƒα ≈ 1:4 (ƒα = 0.5 alpha energy/hot spot energy). The parameter fα can be inferred in ICF experiments by measuring the neutron yield, hot spot size, temperature, and burn width. This ignition threshold is measurable and applicable to all ICF implosions of DT-layered targets both direct and indirect drive. The results of this paper can be used to set the goals of the ICF effort with respect to the first demonstration of thermonuclear ignition.
- Research Organization:
- Univ. of Rochester, NY (United States). Lab. for Laser Energetics
- Sponsoring Organization:
- USDOE National Nuclear Security Administration (NNSA)
- Grant/Contract Number:
- NA0003856
- OSTI ID:
- 1498067
- Alternate ID(s):
- OSTI ID: 1496497
- Report Number(s):
- 2018-220, 1469; PLEEE8; 2018-220, 1469, 2428
- Journal Information:
- Physical Review E, Vol. 99, Issue 2; ISSN 2470-0045
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
Web of Science
On alpha-particle transport in inertial fusion
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journal | June 2019 |
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