Ion-driver fast ignition: Reducing heavy-ion fusion driver energy and cost, simplifying chamber design, target fab, tritium fueling and power conversion

Technical Report · Wed Apr 01 04:00:00 EST 1998

DOI:https://doi.org/10.2172/822253· OSTI ID:822253

Logan, G ^[1]; Callahan-Miller, D; Perkins, J; Caporaso, G; Tabak, M; Moir, R; Meier, W; Bangerter, Roger; Lee, Ed

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1. LBNL Library

Ion fast ignition, like laser fast ignition, can potentially reduce driver energy for high target gain by an order of magnitude, while reducing fuel capsule implosion velocity, convergence ratio, and required precisions in target fabrication and illumination symmetry, all of which should further improve and simplify IFE power plants. From fast-ignition target requirements, we determine requirements for ion beam acceleration, pulse-compression, and final focus for advanced accelerators that must be developed for much shorter pulses and higher voltage gradients than today's accelerators, to deliver the petawatt peak powers and small focal spots ({approx}100 {micro}m) required. Although such peak powers and small focal spots are available today with lasers, development of such advanced accelerators is motivated by the greater likely efficiency of deep ion penetration and deposition into pre-compressed 1000x liquid density DT cores. Ion ignitor beam parameters for acceleration, pulse compression, and final focus are estimated for two examples based on a Dielectric Wall Accelerator; (1) a small target with {rho}r {approx} 2 g/cm{sup 2} for a small demo/pilot plant producing {approx}40 MJ of fusion yield per target, and (2) a large target with {rho}r {approx} 10 g/cm{sup 2} producing {approx}1 GJ yield for multi-unit electricity/hydrogen plants, allowing internal T-breeding with low T/D ratios, >75 % of the total fusion yield captured for plasma direct conversion, and simple liquid-protected chambers with gravity clearing. Key enabling development needs for ion fast ignition are found to be (1) ''Close-coupled'' target designs for single-ended illumination of both compressor and ignitor beams; (2) Development of high gradient (>25 MV/m) linacs with high charge-state (q {approx} 26) ion sources for short ({approx}5 ns) accelerator output pulses; (3) Small mm-scale laser-driven plasma lens of {approx}10 MG fields to provide steep focusing angles close-in to the target (built-in as part of each target); (4) beam space charge-neutralization during both drift compression and final focus to target. Except for (1) and (2), these critical issues may be explored on existing heavy-ion storage ring accelerator facilities.

• Research Organization: Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science (US)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 822253
• Report Number(s): LBNL--51114; HIFAN 1174
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
36 MATERIALS SCIENCE
43 PARTICLE ACCELERATORS
ACCELERATOR FACILITIES
BATTERY CHARGE STATE
DESIGN
DIELECTRIC MATERIALS
ELECTROMAGNETIC LENSES
FUSION YIELD
IGNITION
ILLUMINANCE
ION BEAMS
ION SOURCES
LINEAR ACCELERATORS
PEAK LOAD
POWER PLANTS
STORAGE RINGS
TARGETS
TRITIUM