Vol 45, No 7 (2018)

The results of experimental measurements of the hydrodynamic efficiency of laser plasma for aluminum and copper targets are presented. The studies were performed on the “Kanal-2” laser setup system using the ballistic pendulum method. The pressure in the interaction chamber was 10⁻⁴ Torr, the pendulum length was 145 mm, the mass of the pendulum with a target was 7.2 g. At the half-height pulse duration of 2.5 ns, the power density on the target surface was ∼10¹³ W/cm². In the case of aluminum target, the hydrodynamic efficiency coefficient increased from 1.5% to 4.5% with increasing laser pulse energy from 5 J to 10 J, whereas it remained at the level of 5% for the copper target.

Numerical simulation of blood vessel heating is used to select the most efficient and safe methods of laser treatment of “port-wine stains”. Selective heating under radiation is calculated for a 980-nm diode laser, a Nd:YAG laser, a copper vapor laser (CVL), and a pulsed dye laser (PDL). The energy exposure range (fluence), the diameter and depth of vessels, at which their selective heating to the coagulation temperature is possible, are determined.

Lidar sensing of tectonic aerosol fluctuations in the laser strainmeter–interferometer tunnel during 2017.12–2018.05 at the Schultz cape (131°9′8″ E, 42°34′6″ N) near Vladivostok was performed for the first time to our knowledge. A negative correlation of laser interferometer and aerosol lidar signals was observed during low-frequency Earth crust deformations.

Colloidal solution precipitates obtained during laser ablation of tungsten in water and containing nanostructured metal oxides are studied using X-ray diffraction and scanning electron microscopy. The nanostructure composition and morphology are analyzed. It is shown that the material composing nanostructures is X-ray amorphous, i.e., the particle size does not exceed 1–2 nm. The high degree of the structure surface development implies prospects of their use as substrata when analyzing the composition of various materials by surface-enhanced Raman scattering.