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Title: Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams

Abstract

A hemispherical conically guided indirectly driven inertial confinement fusion capsule has been considered. The fast ignition of the precompressed capsule driven by one or two laser-accelerated proton beams has been numerically investigated. The energy distribution of the protons is Gaussian with a mean energy of 12 MeV and a full width at half maximum of 1 MeV. A new scheme that uses two laser-accelerated proton beams is proposed. It is found that the energy deposition of 1 kJ provided by a first proton beam generates a low-density cylindrical channel and launches a forward shock. A second proton beam, delayed by a few tens of ps and driving the energy of 6 kJ, crosses the low-density channel and heats the dense shocked region where the ignition of the deuterium-tritium nuclear fuel is achieved. For the considered capsule, this new two-beam configuration reduces the ignition energy threshold to 7 kJ.

Authors:
 [1]
  1. Edificio San Roque calle Beni, 4B, Sucre (Bolivia)
Publication Date:
OSTI Identifier:
20860449
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 13; Journal Issue: 12; Other Information: DOI: 10.1063/1.2400592; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BEAM-PLASMA SYSTEMS; CAPSULES; CYLINDRICAL CONFIGURATION; D-T OPERATION; DEUTERIUM; ENERGY SPECTRA; GAUSS FUNCTION; ICF DEVICES; INERTIAL CONFINEMENT; LASERS; MEV RANGE; PROTON BEAMS; PROTONS; SHOCK WAVES; THERMONUCLEAR IGNITION; TRITIUM

Citation Formats

Temporal, Mauro. Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams. United States: N. p., 2006. Web. doi:10.1063/1.2400592.
Temporal, Mauro. Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams. United States. doi:10.1063/1.2400592.
Temporal, Mauro. Fri . "Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams". United States. doi:10.1063/1.2400592.
@article{osti_20860449,
title = {Fast ignition of a compressed inertial confinement fusion hemispherical capsule by two proton beams},
author = {Temporal, Mauro},
abstractNote = {A hemispherical conically guided indirectly driven inertial confinement fusion capsule has been considered. The fast ignition of the precompressed capsule driven by one or two laser-accelerated proton beams has been numerically investigated. The energy distribution of the protons is Gaussian with a mean energy of 12 MeV and a full width at half maximum of 1 MeV. A new scheme that uses two laser-accelerated proton beams is proposed. It is found that the energy deposition of 1 kJ provided by a first proton beam generates a low-density cylindrical channel and launches a forward shock. A second proton beam, delayed by a few tens of ps and driving the energy of 6 kJ, crosses the low-density channel and heats the dense shocked region where the ignition of the deuterium-tritium nuclear fuel is achieved. For the considered capsule, this new two-beam configuration reduces the ignition energy threshold to 7 kJ.},
doi = {10.1063/1.2400592},
journal = {Physics of Plasmas},
number = 12,
volume = 13,
place = {United States},
year = {Fri Dec 15 00:00:00 EST 2006},
month = {Fri Dec 15 00:00:00 EST 2006}
}
  • One- and two-dimensional multigroup radiation hydrodynamics simulations have been performed to investigate the motion of the gold plasma generated at the surface of the embedded gold cone in a re-entrant cone-guided inertial confinement fusion capsule. The effect of deuterium-tritium (DT) ice layers, and other possible tampers, of varying thickness, upon the motion of the gold cone plasma has been investigated. The effect of the x-ray drive spectrum incident upon the ice layer is also explored. Ice is shown to tamp the expansion of the gold cone, and whilst denser materials are shown to be more effective in this role, icemore » does not pollute the ignition region with intermediate-Z ions, which, though preferable to gold contamination, also tend to inhibit the attainment of high fuel-ion temperatures.« less
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  • We report for the first time on full 2-D radiation-hydrodynamic implosion simulations that explore the impact of highly compressed imposed magnetic fields on the ignition and burn of perturbed spherical implosions of ignition-scale cryogenic capsules. Using perturbations that highly convolute the cold fuel boundary of the hotspot and prevent ignition without applied fields, we impose initial axial seed fields of 20–100 T (potentially attainable using present experimental methods) that compress to greater than 4 × 10{sup 4} T (400 MG) under implosion, thereby relaxing hotspot areal densities and pressures required for ignition and propagating burn by ∼50%. The compressed fieldmore » is high enough to suppress transverse electron heat conduction, and to allow alphas to couple energy into the hotspot even when highly deformed by large low-mode amplitudes. This might permit the recovery of ignition, or at least significant alpha particle heating, in submarginal capsules that would otherwise fail because of adverse hydrodynamic instabilities.« less
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  • Abstract not provided.