Compression and burning of a direct-driven thermonuclear target under the conditions of inhomogeneous heating by a multi-beam megajoule laser

Abstract

The paper is devoted to the numerical and theoretical study of compression and burning of a thermonuclear target under the conditions of inhomogeneous heating due to direct irradiation with a multi-beam megajoule laser facility. The two-dimensional distribution of absorbed laser energy has been numerically calculated taking into account refraction and various known factors of the violation of irradiation homogeneity. The limits of the violation of irradiation uniformity caused by these factors, which are acceptable for spark ignition of the target irradiated with 192 laser beams of the modern megajoule facilities, are determined. The target offset relative to the aiming point of the laser beams should not exceed 2% of the target radius, mispointing of the beams (5% of the target radius), mistiming of the laser pulses (3% of the pulse duration) and energy imbalance among the laser clusters (12%). These values exceed the permissible deviations for the laser facility being developed within the frameworks of the project.

Fast-electron maintaining a high shock-ignition gain with a significant decrease in the laser pulse energy

“…The electron component is described by thermal (as for ions) and elastic components. Semi-empirical relations are used to describe the elastic component [52].…”

Quasi-three-dimensional hydrodynamics of the corona region of laser irradiation of a slab

“…In recent years, the interaction between lasers and slab targets has been a focal point of research, playing a crucial role in reproducing research in cutting-edge fields such as laboratory astrophysics [1][2][3][4][5][6][7][8][9] and inertial confinement fusion (ICF). [10][11][12][13][14][15][16][17][18][19][20] As an indispensable research tool, the laser-target interaction method has aided the performance of related research in many fields. From both experimental and simulation aspects, whether it is the law of evolution of the electromagnetic field [1] or the change of the topological structure of magnetic reconnection, [2] the outflow of magnetic reconnection, [3] the loop-top x-ray source [4] and guiding field magnetic reconnection [5] realized using high-energy laserdriven slab targets in the laboratory, are all based on threedimensional laser irradiation slab target experiments.…”

Measurement of amplified binary-modulated chirped laser pulses generated by different acousto-optic pulse shaping algorithms

“…Chirped laser pulses and pulse trains can improve efficiency of material ablation and nanoparticle generation via tailoring specific thermodynamic states of irradiated matter [4][5][6][7]. It is also argued that using spreadspectrum pulses instead of amplitude-modulated quasimonochromatic ones can sufficiently suppress laser plasma instabilities and induced Brillouin scattering in fast ignition fusion schemes [8][9][10][11].…”