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Solar Plasma propulsion methods proposed by the Air Force have lead to the study of high temperature optical absorption of metal vapors. The Plasma Spectroscopy Cell in the Phillips Laboratory at Edwards AFB CA has been used to obtain an abundance of absorption spectra at temperatures approaching 2000 K and pressures of one atmosphere for lithium and sodium metal vapors. Tentative assignments of molecular transitions are improved upon by use of modern computational techniques for generating intensities of molecular transitions which possibly have been observed. Identification of contributing molecular transitions to overall absorption of radiant energy assists the efforts to develop propulsion methods which rely on the direct absorption of solar energy. jg, Performed in collaboration with Connecticut Univ. and Iowa Univ.

Laser Science is an emerging technical area with a stong interdisciplinary flavor. It is based on atomic and molecular physics, chemical physics, condensed matter physics, optical physics and engineering, plasma physics, physical chemistry, photochemistry, materials science and engineering, electrical engineering, gaseous electronics, quantum electronics, and electro-optics. At the core of laser science are the mechanisms of the lasers themselves and the interaction of the laser photons with matter (spectroscopy and photoprocesses). Surrounding this core is the wide spectrum of scientific applications of lasers, not only in the disciplines mentioned above, but also in virtually every other area of science and technology. The primary purpose of the conference is to survey annually both the laser and spectroscopy/photoprocesses core areas and a wide variety of selected scientific applications of lasers.

This project constructed and studied a laser trap for neutral atoms, initially potassium (K). At low densities, such a trap could be used to address a number of fundamental questions, e.g. the interaction of an individual atom with an electromagnetic field, collision dynamics and recombination. The feasibility and limitations of a purely laser trap concept, a corner cube trap , for trapping neutral K atoms are studied. The confinement of the atoms in the two dimensions perpendicular to the laser is provided in the cavity of a newly constructed high power alexandrite laser operating in the (doughnut mode) tuned slightly to the blue side of the resonance line of the K atom. By reflecting the laser back on itself with two mirrors, one caps the ends of the cylindrical trap, resulting in a slightly weaker end plug. Examined are various loss mechanism for the trapped atoms. In particular, K atoms are lost to the trap if they are multiphoton ionized, if they are heated by absorption and emission of many photons, if they simply have much higher energy than the vast majority of other atoms at 1.5 K, or if they recombine with He to form KHe (or KHe2, etc).

The annual International Laser Science Conferences have been established to survey the core laser science areas including lasers and their properties, spectroscopy, laser-induced processes, and a selection of laser applications. This meeting is a Topical Conference of the American Physical Society (APS) and is also the annual meeting of the APS Topical Group on Laser Science. Earlier ILS Conferences were held in Dallas in 1985 (ILS-I) and in Seattle in 1986 (ILS-II). ILS-III was held in Atlantic City, New Jersey, November 1-4, 1987, with the co-sponsorship of the Optical Society of America.

Symposia Contents: Tunable Solid State Lasers; Lasers and Coherent Sources; Solid State Sources; Novel Laser Systems-Modifications to Visible, Ultraviolet, and X-Ray Lasers; Spectroscopy of Materials for Solid State Laser Systems; Modeling of Lasers and Laser Dynamics; Nonlinear Optical Phenomena and Applications; Squeezed States and Quantum Optics; Nonlinear Optical Phenomena in Atomic Vapors; Nonlinear Optics in Semiconductors; Short Pulse Lasers and Applications; Condensed Matter, Surface, and Particle Spectroscopy with Emphasis on Laser-Surface Interactions; Laser-Condensed Matter Interactions; Applications of Laser/Surface Interactions; Laser Modification of Surfaces; Surface Nonlinear Optics; Laser Ionization, Ablation and Deposition; Atomic, Molecular, and Ionic Spectroscopy; Energy Resolved Ionization and Fragmentation Processes in Atoms and Small Molecules; Ionization Processes and Ion Spectroscopy of Polyatomic Species; Interaction of Strong Optical Fields with Matter; Experiments with Laser Cooled and Trapped Atoms; High Resolution Spectroscopy-From Atoms to Polyatomic Molecules; State-Specific Photophysics and Photochemistry; Diagnostic and Analytical Applications of Lasers; Advances in Raman Spectroscopy; Lasers and Chromatography; Advances in Photothermal Spectroscopy; Lasers in Trace Analysis; Lasers in Combustion Analysis; and Advances in Plasma Diagnostics. (jhd), Availability: American Institute of Physics, 335 E. 45th St, New York, NY 10017 HC $85.00. No copies furnished by DTIC.

The purpose of this project is to construct and study a laser trap for neutral atoms, initially potassium (K). At low densities, such a trap could be used to address a number of fundamental questions, e.g., the interaction of an individual atom with an electromagnetic field, collision dynamics and recombination. The feasibility and limitations of a purely laser trap concept, a corner cube trap, are studied for trapping neutral K atoms. The confinement of the atoms in the two dimensions perpendicular to the laser will be provided in the cavity of a high power alexandrite laser operating in the ('doughnut mode') tuned slightly to the blue side of the 4s 2S1/2 to 2P3 resonance line of the K atom. By reflecting the laser back on itself with two mirrors, one caps the ends of the cylindrical trap, resulting in a slightly weaker end plug. This trap concept employs not laser cooling, but rather counterstreaming 4He atoms which are cooled to about 1.5 K, to drastically cool the K atoms to thermal energies well below the trap depth (expected to be about 10 K). Various loss mechanisms for the trapped atoms are studied. In particular, K atoms can be lost to the trap if they are multiphoton ionized, if they are heated by absorption and emission of many photons ('recoil' or 'diffusional' heating), if they simply have much higher energy than the vast majority of other atoms at 1.5 K, or if they recombine with He atoms to form KHe (or KHe2, etc.).

The purpose of this project is to construct and study a laser trap for neutral atoms, initially potassium (K). At low densities, such a trap could be used to address a number of fundamental questions, e.g. the interaction of an individual atom with an electromagnetic field, collision dynamics and recombination. We have studied the feasibility and imitations of a purely laser trap concept, a 'corner cube trap', for trapping neutral K atoms. The confinement of the atoms in the two dimensions perpendicular to the laser is provided in the cavity of a newly constructed high power alexandrite laser operating in the CW TEM*01 mode ('doughnut mode') tuned slightly to the blue side of the resonance line of the K atom. By reflecting the TEM*01 laser back on itself with two mirrors, one 'caps' the ends of the cylindrical trap, resulting in a slightly weaker end plug. Keywords: Laser trap, Neutral atom trap, Multiphoton ionization, Atomic recombination. (MJM)

Contents: Limits to Laser Advancements; Advanced Lasers and Coherent Sources; Nonlinear Optical Phenomena and Applications; Atomic, Molecular, and Ionic Spectroscopy; Condensed Matter, Surface, and Particle Spectroscopy; Laser Photochemistry and Photophysics; Diagnostic and Analytical Applications of Lasers; Laser Research and Techniques in Medicine and Biology.

Progress is described on study of a new class of potential excimer lasers based on diffuse bands of the alkali metal vapors. In particular, the violet diffuse bands of sodium vapor and the yellow diffuse bands of potassium vapor have been shown by detailed modeling of single vibrational-rotational level emission to be each composed of overlapping singlet and triplet 'excimer' emission continua of the diatomic molecule. The gain and low absorption loss previously found in the violet and yellow with laser optical pumping of sodium vapor and potassium vapor, respectively, have been quantitatively examined. Prospects for laser oscillation appear to be good at low pressures where quenching is not dominant. Free-bound-free spectra (which include only the triplet portion of the diffuse bands) have been produced and analyzed in sodium, potassium, rubidium and cesium. Keywords: Excimer, Lasers, Singlet.

This Proceedings volume is not intended to replace the publication of new and complete research results in the technical journals that cover our fields. Instead, the brief accounts of research from the contributed and some of the invited papers are intended to be focused on providing entry-level information about the research topic chosen, with just enough description aided by a listing of the key references to enable the reader to (1) understand the basis of what has been accomplished, and (2) know where to look in order to find more detailed information. Others of the invited papers, the plenary lectures, and an accounting of the initial panel discussion are directed more at providing reviews of technical areas as well as original results, and in some instances include historical perspectives and thoughts on future directions. Keywords include: Laser science, Lasers, Coherent sources, Optics, and Spectroscopy.

This book discusses: Limits to Laser Advancements-Fundamental and Otherwise, Advanced Lasers and Coherent Sources; High Energy Laser Overviews; Gamma Ray Lasers; Novel Solid-State Lasers; Enhancement of Free Electron Laser Performance; Ultrafast Short Wavelength Light Sources and Techniques; Applications of Ultrashort Wavelength Lasers; Measurements of Subpicosecond Laser-Produced Plasmas; Nonlinear Optical Phenomena and Applications; Atomic, Molecular, and Ionic Spectroscopy; Condensed Matter, Surface, and Particle Spectroscopy; Laser Photochemistry and Photophysics; Diagnostic and Analytical Applications of Lasers; Laser Research and Techniques in Medicine and Biology.