Investigation of low-coherence laser radiation interaction with different materials

The paper presents the results of experiments on the interaction of low-coherence laser radiation with low density volume-structured materials and solid-state density materials, performed at the facility “KANAL-2” [1]. The data on scattering, absorption, and transport of low-coherence heating laser radiation through plasmas from low-density volume-structured materials and solid density materials have been analyzed. The experiments have demonstrated that laser radiation of low coherence effectively interacts with low density materials, and materials of solid-state density

The influence of underdense polymer target with/without high-Z nanoparticles on laser radiation absorption and energy transport

Fabrication methods for low-density fine-structure (cell size $<$1 $\mu$m) 3-D networks of cellulose triacetate (TAC) are developed. Target densities ranged 4-20 mg/cc, similar polymer structures were produced both with no load and with high-Z cluster dopant with concentration up to 30%. Foams of varying density down to 0.25 plasma critical density at the third harmonic of iodine laser wavelength are supplied for laser shots. Experiments with underdense foam targets with and without clusters irradiated on the PALS laser facility are analyzed preliminary, showing strong influence of target structure on process of laser light absorption. Heat and radiation transport in such targets are considered

Study of physical processes in laser-irradiated porous targets of different microstructure

New results obtained in experiments on laser irradiation (${\rm I}=10^{14}$ W/cm$^{2}$, ${\rm \lambda} =1.055 {\rm \mu}$m) of low-density (1-30 mg/cm$^{3})$ fibrous and foam-like materials are presented and discussed. The effect of low-density material microstructure of irradiated samples on physical processes in high-temperature plasma was investigated. Using a variety of complementary X-ray and optical methods the pronounced effect of material microstructure on the parameters and dynamics of produced plasma was found

Laser study into and explanation of the direct-indirect target concept

The idea of direct-indirect target is experimentally tested with planar targets from LPI made of low-density metal foam (nanosnow) or of nanoparticles (30%) in plastic aerogels. The laser experiments in BARC have shown that compared to plain targets the foams of/with nanoparticles demonstrate: 1) better x-ray emissivity ; 2) smoother energy distribution over the target surface; 3) material flow from low-density wall being slower and more uniform; 4) active transverse energy transport over the target plane. These properties could be useful for hohlraums and direct-indirect concept