The possibility of observing the stimulated de-excitation of nuclear isomers (SDENI) in plasma (plasma lifetime ∼1.5 ps, temperature of electrons ∼ 10 keV) formed by the impact of a high-power laser pulse (∼10 18 W cm −2 ) on a target is studied experimentally. Preliminary experiments are carried out with the 110 m Ag ( T 1/2 = 250 days) and 186 m Re ( T 1/2 = 2 × 10 5 years) isomers. A weak SDENI effect is observed only for the 110 m Ag isomer on a platinum backing.

This paper presents the optical layout and composition of a system for automatically adjusting the multipass power module of a next-generation laser apparatus. An adjustment technique based on near-field and far-field markers is described. A control program under the Astra Linux operating system is described for the automatic-adjustment system.

This paper discusses the features of using a small tool to shape the working surfaces of compact disk-shaped active elements. The results of measuring the fine-structure error are presented. An algorithm is presented for numerically modelling the wave-front distortions of a beam transmitted through an arbitrary number of elements that contain fine-structure error, along with the results of the modelling. (C) 2010 Optical Society of America.

This paper presents the results of studies of the acceleration of macroparticles consisting of fragments of matter from the back side of a solid target when its front surface is irradiated with a picosecond laser pulse with intensity 10(13) - 10(15) W/cm(2). It is experimentally shown that there are optimal conditions for maximizing the spalling momentum of the target fragments, depending on its thickness and the intensity of the laser pulse on the front surface. The focusing of melted fragments of the substance, split off from the back surface of a target made in the form of a hemisphere, is experimentally demonstrated. The spalling momentum from such a target is greater than the momentum from a flat target of the same thickness by a factor of 6-7. (C) 2009 Optical Society of America.

It was found that maximum particle output and best possible spatial uniformity of proton beam took place for two-layer target when the front layer was the high-Z film. It was shown that the ion radiography of the convenient objects with using the two-layer targets allow to get the projecting pictures with high spatial resolution that was about one micron. Threshold spatial sensitivity of proton radiography is estimated.

It was found that maximum particle output and best possible spatial uniformity of proton beam took place for two-layer target when the front layer was the high-Z film. It was shown that the ion radiography of the convenient objects with using the two-layer targets allow to get the projecting pictures with high spatial resolution that was about one micron. Threshold spatial sensitivity of proton radiography is estimated.

Laser plasma produced with high-intensity picosecond laser pulse like proton source for radiography was investigated. It was found that maximum particle output and best possible spatial uniformity of proton beam took place for two-layer target when the front layer was the high-Z film. It was shown that the ion radiography of the convenient objects with using the two-layer targets allow to get the projecting pictues with high spatial resolution that was about one micron. The explanation of such high spatial resolution is in laminar motion of ion flow. Threshold spatial sensitivity of proton radiography is estimated.

The proton and deuteron yields from thin targets irradiated by a picosecond laser pulse with an average radiation intensity of ≤4×10 18 W/cm 2 at the target were measured in the megaelectron-volt energy range. A ring structure was observed for the outgoing ions, and the angular ion-beam divergence was found to be extremely small (0.5°). The fast-ion generation mechanism allowing for the appearance of ring structure is discussed, and the characteristic energies and spatioangular ion-beam distribution are estimated.

A mirror-lens objective has been developed that focuses a powerful laser beam with a planar wavefront into a straight line 10 mm long. The objective is intended for the creation of extended plasma objects. The construction involves an improved version of Maksutov's meniscus system, based on a toroidal mirror. A sample with an effective diameter of 130 mm and a relative aperture of 1:2.4 has been fabricated and investigated.

A remote systems has been developed for the adjustment of the Luch 16 kJ, four-channel Nd-glass laser apparatus. The adjustment methods are based on comparison of the position of the beam of an adjusting laser-relative to stops in the near and far fields. The elements of the system are cw lasers, beam-position monitoring sensors based on controllable television (TV) cameras, high precision rotating mirror mounts with stepper-motor. drives, motor controllers, TV switches, and a controlling computer. The results of theoretical studies of the adjustment system are presented. Ways are considered of converting the remote adjustment system to an automatic adjustment system. (C) 2003 Optical Society of America.

Results of fast light ion yield measurements are presented. Laser-plasma experiments were carried out on picosecond laser PROGRESS-P at laser intensities on a target to be 1 ÷ 4•1018 W/cm2. Ring image and extremely small angular divergence of fast ion beam were found. Hard ions with energy more than 8 MeV were recorded. Model of fast ion generation is discussed and typical energy and spatial distribution of fast ion extension are estimated.

This paper discusses features of the fabrication of focusing objectives based on an off-axis parabolic mirror with large asphericity (more than 350 mum) and a large asphericity gradient (about 20 mum/mm). The objectives are intended to concentrate the radiation of a picosecond laser. The effective diameter of the objectives is 145 mm, and the relative aperture is 1: 1.4. The aspheric surface is fabricated by automatically processing the optical surfaces with a small tool on an AD-1000 machine. Up to 83% of the energy of a plane wave at the fundamental frequency of a neodymium laser is concentrated at a focal point 9 mum in diameter. (C) 2002 Optical Society of America.

The interaction of a 1053 nm picosecond laser pulse with a solid target for focused intensities of up to 10(19) W/cm(2) are studied by measurements of the absorption of the laser light in the plasma and by measurements of the production of hard X-rays. Absorption measurements are made by collecting the scattered light in set of calorimeters. Light scattered in backward and specular directions is collected separately. Measurements are presented for both high and low Z targets. Hard X-ray spectrum in range 15 - 1000 keV and hot electron production in range 1 - 22 MeV are measured using a multichannel filter/scintillator and filter/semiconductor spectrometers. Spatial parameters of fast ions are studied.

Results are presented from an investigation of the hard X-ray spectrum and the parameters of fast particles in experiments on the interaction of laser pulses with solid targets in the PROGRESS-P facility at laser intensities of up to 5×10 18 W/cm 2 on the target surface. The maximum energy of fast electrons obtained from direct measurements is found to be 8–10 MeV.

The scattering and absorption of a high-power picosecond laser pulse by a solid target were investigated experimentally making use of the 'Progress-P' Nd:glass laser facility (λ = 1053 nm, τ = 1.4 ps) at radiation intensities I = 1016 — 1019 W cm-2 on the target surface. It was found that, for I ≤ 1017 W cm-2, more than 30% of the intensity of the scattered light was contained in the specularly reflected component. The absorption coefficient of the laser radiation with intensities ranging from 1018 to 1019 W cm-2 was higher for targets made of materials with higher atomic numbers.