Twenty times lower ignition threshold for laser driven fusion using collective effects and the inhibition factor

Abstract

Hydrodynamic analysis for ignition of inertial fusion by Chu [Phys. Fluids 15, 413 (1972)] arrived at extremely high thresholds of a minimum energy flux density E* at 4×108J∕cm2 which could be provided, e.g., by spark ignition. In view of alternative schemes of fast ignition, a re-evaluation of the early analysis including later discovered collective stopping power and the inhibition factor results in a 20 times lowering of the threshold for E*.

Avalanche boron fusion by laser picosecond block ignition with magnetic trapping for clean and economic reactor

“…This was the main reason to work with laser pulses of nanosecond duration and to use the thermal processes of ablation, compression, and thermonuclear ignition for generating fusion power. These conditions changed with the discovery of CPA [14,15] and the updating of the computations of the fusion reactions based on the same hydrodynamic conditions as [32] arrived at the same result of Equation (5) for DT fusion [34] . Updating by using collective effects and inhibition of thermal conductivity at inhomogeneous plasmas resulted in a reduction of the threshold E o * to lower values up to a factor 20 [34] .…”

“…These conditions changed with the discovery of CPA [14,15] and the updating of the computations of the fusion reactions based on the same hydrodynamic conditions as [32] arrived at the same result of Equation (5) for DT fusion [34] . Updating by using collective effects and inhibition of thermal conductivity at inhomogeneous plasmas resulted in a reduction of the threshold E o * to lower values up to a factor 20 [34] . These results were confirmed [18] with deriving a number of further details by using a basically different genuine multi-fluid hydrodynamic code [35,36] .…”

“…In difference to the computations with the single fluid hydrodynamics [6,16,34,37] , when performing the computations with the much more detailed genuine two-fluid hydrodynamics [35,36] , the properties of the Rankine-Hugoniot shock generation were reproduced for HB11 in a more general way showing the plasma collision generated broadening of the shock front, the very high internal electric fields and their decay, and their delayed built-up within hundreds of picoseconds after the picosecond laser pulse initiation [17] .…”

Fusion energy using avalanche increased boron reactions for block-ignition by ultrahigh power picosecond laser pulses

“…Further, the stopping power had to use the Gabor collective model at this high plasma densities and not the Bethe-Bloch binary collision model. After this updating, the ignition thresholds for the fusion flame arrived at up to 20 times lower values of E * (Hora et al, 2008). After initial results with one-fluid hydrodynamics (Hora, 2009) were performed it was important to receive more information from applying the genuine two-fluid hydrodynamics Fig.…”

“…The result was, however, that the ps laser pulses have at least a minimum energy flux density of few E * =10 8 J/cm 2 . Updating the theory (Hora et al, 2008) led to a reduction of E * by up to a factor 20. First we report block-ignited fusion results for DT fusion before continuing about HB11.…”