Unique properties of laser radiation including its monochromatic properties, polarization, high spectral intensity, coherence, narrow beam divergence, the possibility of controlling the pulse duration and radiation spectrum and, finally, the fact that extremely high power and energy create very favorable conditions for the extensive application of lasers to communi cation systems, systems for the lidar sensing and ultra-high-precision ranging, navigation, remote monitoring of the environment, and many other systems operating in the atmosphere. The operative efficiency of the above systems depends significantly on the state of the atmosphere and the corresponding behavior of laser radia tion propagating through it. This circumstance has stimulated the studies of the above regularities during the passt 10-15 years. For the investiga tions to be carried out the scientists were forced to develop new theories and methods for studying the problem experimentally. Moreover, during such investigations some previously unknown phenomena were observed, among them the nonlinear effects accompanying high-power laser radiation propagating through the atmosphere are of paramount importance. Among the nonlinear effects caused by high-power laser radiation inter action with the atmosphere, the effects accompanying the propagation of high-power radiation through the atmospheric aerosols are of particular interest. Aerosols always occur in the atmosphere. It should be noted that the microphysical and optical characteristics of atmospheric aerosols vary widely, this fact causes a great variety in the features of their inter action with radiation.

This report results from a contract tasking the Institute of Atmospheric Optics, Siberian Branch, as follows: the contractor will investigate theoretically the interaction between femtosecond propagation effects and atmospheric turbulence, supercontinuum emission (spectral broadening), nonlinear scattering by atmospheric aerosols, and theoretical upper and lower limits for nonlinear propagation effects. The specific project objectives are as follows: (1) The theoretical study of powerful femtosecond laser pulse filamentation in the turbulent atmosphere; (2) Researching the supercontinuum cone emission mechanism by numerical simulation of high-power femtosecond laser pulse propagation in the atmosphere; and (3) The theoretical and experimental study of the fundamental problems of scattering of a high-power femtosecond pulse in the atmosphere: nonstationary light scattering in gases and aerosols; nonlinear inelastic nonstationary light scattering by aerosol particles. (26 figures, 73 refs.).

High resolution atmospheric transmittance curves are presented for the spectral region 320 to 13,200/cm (0.7576 to 31.25 micrometers). These spectra are useful as a guide for selecting laser wavelengths for atmospheric propagation studies in this spectral region. In addition, this report provides attenuation coefficients for those lines of the CO, HF, DF, and CO2 laser systems which suffer the least atmospheric attenuation. A new aerosol model is introduced here, taking into account recent measurements of the complex index of refraction of aerosol particles. (Author).

The book introduces optical wave propagation in the irregular turbulent atmosphere and the relations to laser beam and LIDAR applications for both optical communication and imaging. It examines atmosphere fundamentals, structure, and content. It explains specific situations occurring in the irregular atmosphere and for specific natural phenomena that affect optical ray and laser beam propagation. It emphasizes how to use LIDAR to investigate atmospheric phenomena and predict primary parameters of the irregular turbulent atmosphere and suggests what kinds of optical devices to operate in different atmospheric situations to minimize the deleterious effects of natural atmospheric phenomena.

Effects of High-Power Laser Radiation describes the interactions between high-power laser beams and matter. This book is divided into eight chapters that particularly focus on interactions such as heating, melting, vaporization, and plasma production. The opening chapters examine the laser properties, types, measurement techniques, and safety aspects. The succeeding chapters deal with a variety of physical phenomena and mechanisms of laser-induced particle emission, as well as the initiation and development of gas breakdown phenomena. Other chapters explore the effects and damage of various interactions in transparent materials and on biological systems. The final chapter looks into the practical applications of the various laser effects to diverse technological fields. This book will prove useful to scientists interested in the physical phenomena of laser effects and engineers interested in practical applications of laser effects.

A detailed discussion is presented of various theories, experiments, and models pertinent to atmospheric effects on the transmission of low-power laser radiation. The effects of molecules, aerosols, and turbulence and their levels in the atmosphere are considered. Specific conclusions and recommendations are given with regard to the state of knowledge in this field, and to models that can be used to predict atmospheric effects that are relevant to comprehensive personnel safety standards.