Московский физико-технический институт, Московская обл., г. Долгопрудный, Россия Экспериментальные исследования генерации ударных волн в поликристаллических мишенях проводились на мощной Nd-лазерной установке «Сатурн» при значениях интенсивности в пределах 10 12-10 13 Вт/см 2. Обосновано применение теоретической модели трансформации энергии импульсного лазерного источника в энергию ударной волны при абляционном процессе на поверхности мишени в режиме гидродинамического воздействия. Проведено сравнение рассчитанных и измеренных параметров образующихся кратеров для различных типов мишеней. Ключевые слова: лазерное моделирование ударных процессов, плазменный факел, ударная волна, лазерная абляция, сверхскоростной микрометеоритный удар.

The present review is of the experimental investigations on laser-plasma interaction being carried out in past years at IAE. Experiments were conducted on the “Mishen” facility. The laser system of Mishen consists of two channels with output beam parameters as follows: the main beam—output energy 100–200 J (λ = 1.054 μm) in 3-ns pulse, divergence ∼2 × 10-4 rad, contrast ratio ∼106, power density at the target surface ∼1013–1014 W/cm2; the diagnostic beam–output energy 10–20 J (λ = 1.054 μm) and 5–10 J (λ = 0.53 μm) in 0.3-ns pulse, divergence ∼10-4 rad, power density 1013 - 1014 W/cm2. Our aim in this experiment is to study the different aspects of the ICF processes in flat geometry. The main issues of our studies are hydrodynamic aspects, including acceleration efficiency, high-velocity impact in cascade targets, hydrostability, and X-ray physicsconversion efficiency, heat transfer, and X-ray-driven targets.

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The key physical processes of the laser fusion are well known and include the laser beam absorption, the heat transfer from the absorption zone to the ablation surface, the shell ablation acceleration and fusion fuel compression, the initiation of an effective thermonuclear burn. The first and second issues are investigated in detail on the small and moderate size facilities and high level of understanding is achieved on both phenomena. On the other hand, to study the thermonuclear burn seriously the large scale experiments should be carried out on the facilities of the next generation. Thus the efficiency and stability of the shell acceleration are today the main objects of experimental investigations in the majority of the laser fusion research laboratories. This paper is devoted to the development of the diagnostic methods just for studies of these problems.

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