[en] Simulations of gain in recombining laser-produced plasma of Li-like ions of aluminum were performed using the 2-D code GIDRA-2. Symmetrical 4-beam scheme of fiber irradiation was modeled in accordance with experimental arrangement described in Ref. (1). These simulations show good agreement with earlier 1-D simulations for optically thin plasma. Maximal angle-averaged value of gain on 3d_5/2-4f_7/2 transition in Li-like aluminum calculated using Sobolev approximation for photon escape probability and the Doppler line profile was 0.95 cm^-1. These 2-D simulations also show more realistic laser energy absorption (25-30% in 2-D simulations compared to nearly 90% in 1-D simulations and 6% in experiments)

[en] CO₂-laser-produced plasma ion component parameters were studied for aluminium and lead targets at laser intensity of P = 4x10¹³ W cm^-2 and pulse duration of τ = 15 ns experimentally and numerically. Angular dependences of ion number density for different charge states, average velocity and its spread were measured by time-of-flight method. Ion charge state distribution shows high-charge and low-charge state groups at normal expansion direction. Ions in these groups have different average expansion velocity and longitudinal velocity spread. Angular distribution of high-charge states is narrower than that of the low-charge state ion group, maximum yield of low-charge states occur at some angle from normal. For Al target results show similar trends as for Pb target, but simulations have indicated that the effect of laser ponderomotive force is more pronounced in this case

[en] A CO₂ laser system with self-modulation of the intracavity losses was developed. This system was capable of generating efficiently pulses free of a radiation 'tail' typical for CO₂ lasers. A simple method was used to detect the optical inhomogeneity of the medium of a gas-discharge TEA module. The results of the measurements are presented. (lasers)

[en] In the system consisting of a master oscillator, a three-pass telescopic amplifier, and saturable absorbing cells, CO₂ laser pulses with an energy of 100 J and duration variable from 15 to 80 ns were obtained. A theoretical model for the calculation of interaction of CO₂ laser radiation with resonance absorbing and amplifying media was developed. The system consisting of an absorber saturated at the leading edge of the pulse and an amplifier working in the deep-saturation mode was shown to provide a considerable increase in the gain and pulse compression. (lasers)

[en] Resonant and intercombination spectral lines formation of He-like magnesium is analyzed both experimentally and numerically. It is shown that in plasma created by XeCl laser at flux density 8·10¹² W/cm² the peak of electron temperature is placed downstream from the critical surface at density significantly smaller than critical, and radiation in both resonant and recombination lines is also produced by the plasma region with density below critical. Simulations also show significant line radiation at large distances (1-2 mm) from the target as it was observed in experiments. This secondary peak is produced by a compression wave forming near the plasma front. As opposite, radiation in these lines in plasma created by Nd-glass laser at flux density 5·10¹³ W/cm² comes from the plasma region placed deeper than the critical surface and has no tail at large distances