Download or read book Line Intensities for Diagnosing Laser produced Plasmas written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We have measured relative line intensities of the K x-ray spectra of Si, Cl, and Ca from laser-produced plasmas to assess their usefulness as a plasma diagnostic. The different elements are added at low concentrations to CH disks which are irradiated at 5 x 1014 W/cm2 with a 0.53 .mu.m laser pulse of 20 Joules at 1 nsec. The concentration of each element is kept low in order not to change the Z of the plasma, and therefore the plasma dynamics. The various spectra are measured with a time-resolved spectrograph to obtain line intensities as a function of time over the length of the laser pulse. These relative intensities of various He-like and H-like lines are compared with calculations from a steady-state level population code. The results give good consistency among the various line ratios. Agreement is not as good for analysis of the Li-like satellite lines. Modelling of the Li-like lines need further investigation. 10 references, 9 figures.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 1124 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Energy Research Abstracts written by and published by . This book was released on 1990 with total page 840 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Diagnostics of Colliding Laser Produced Plasmas written by Colm Fallon and published by . This book was released on 2013 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recently prepulse techniques such as dual-pulse laser-induced breakdown spectroscopy (DP-LIBS) have emerged as commonly used analytical techniques for qualitative and quantitative elemental investigations in various research fields and disciplines such as industrial, defense and medical applications. The performance of the DP-LIBS technique is strongly dependent on the choice of the experimental conditions. The key parameters that affect its performance are the target properties, laser wavelength, pulse duration, energy and spot-size, interpulse delay times, delay time of observations, ambient background gas pressure and geometrical setup of the optics. The DP-LIBS approach provides significant enhancement in the intensities of emission lines and their lifetimes, up to two orders of magnitude greater than conventional single pulse laser induced breakdown spectroscopy. The aim of the work presented here is to further advance prepulse techniques, as well as other methods to control species density, with a view to optimise emission in the visible wavelength range. In particular, a new technique involving reheating the stagnation layer formed at the collision front between two (or more) colliding plasmas is explored. Spatially and temporally resolved imaging and spectroscopy of the interaction region between two colliding plasmas are employed to demonstrate for the first time that pumping of an optimised stagnation layer significantly increases the intensity emission and duration of selected spectral lines. This technique offers the promise of tunable density and tunable energy (temperature) plasmas. It will potentially increase both the lifetimes and intensities of spectral lines in laser produced plasmas by creating relatively low density - high energy plasmas which can overcome the problem of flux loss due to opacity, which leads to the attenuation of discrete emission lines with a concomitant reduction in line contrast, signal-to-noise ratio (SNR) and signal-to-background ratio (SBR). The latter is a key parameter in determining the limit-of-detection (LOD) of the LIBS technique. Other applications of stagnation layers include the development of 'target fuel' for Extreme UltraViolet (EUV) and X-ray light sources with an especial emphasis on generating high repetition rate, preheated droplet-like targets that can compete with the current liquid drop targets. The latter suffer from clogging at the jet nozzle due to adiabatic expansion freezing. Also, unlike stagnation layers the basic parameters of the droplet fuel cannot be easily varied in the way that stagnation layers allow.

Download or read book Diagnostics Of Laboratory And Astrophysical Plasmas Using Spectral Lineshapes Of One Two And Three electron Systems written by Eugene Oks and published by World Scientific. This book was released on 2017-03-24 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents an advanced tool for experimentalists using spectral lineshapes for diagnostics of laboratory or astrophysical plasmas, and for theorists helping the experimentalists in interpreting the experimental line profiles. It significantly expands the scope of parameters of plasmas and/or fields in it that can be measured. For some parameters, the book presents new, more advanced diagnostic methods than the methods covered in the previous books.

Download or read book Diagnostics for Fusion Experiments written by E. Sindoni and published by Elsevier. This book was released on 2013-10-22 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diagnostics for Fusion Experiments provides information pertinent to the fundamental aspects of plasma physics. This book presents the requirement in measuring electron and ion temperatures at the multi-key level. Organized into four parts encompassing 36 chapters, this book begins with an overview of the principles and methods by which analysis of the fast neutrals obtained by charge exchange in the plasma volume can be utilized to obtain the plasma ion temperature. This text then examines the use of active particle beam systems in plasma diagnostics. Other chapters consider the source function for production of fast neutrals in Tokamak plasma. This book discusses as well the special diagnostic needs of mirror machines, with focus on diagnostics involving the higher-power neutral beams used with them. The final chapter deals with the standard mirror fission-fusion hybrid, tandem mirror, and the field-reversed mirror. This book is a valuable resource for experimental physicists and research workers.

Download or read book ERDA Energy Research Abstracts written by and published by . This book was released on 1989 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Feasibility of Measuring Density and Temperature of Laser Produced Plasmas Using Spectroscopic Techniques written by and published by . This book was released on 2008 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A wide variety of experiments on the Z-Beamlet laser involve the creation of laser produced plasmas. Having a direct measurement of the density and temperature of these plasma would an extremely useful tool, as understanding how these quantities evolve in space and time gives insight into the causes of changes in other physical processes, such as x-ray generation and opacity. We propose to investigate the possibility of diagnosing the density and temperature of laser-produced plasma using temporally and spatially resolved spectroscopic techniques that are similar to ones that have been successfully fielded on other systems. Various researchers have measured the density and temperature of laboratory plasmas by looking at the width and intensity ratio of various characteristic lines in gases such as nitrogen and hydrogen, as well as in plasmas produced off of solid targets such as zinc. The plasma conditions produce two major measurable effects on the characteristic spectral lines of that plasma. The 1st is the Stark broadening of an individual line, which depends on the electron density of the plasma, with higher densities leading to broader lines. The second effect is a change in the ratio of various lines in the plasma corresponding to different ionization states. By looking at the ratio of these lines, we can gain some understanding of the plasma ionization state and consequently its temperature (and ion density when coupled with the broadening measurement). The hotter a plasma is, the higher greater the intensity of lines corresponding to higher ionization states. We would like to investigate fielding a system on the Z-Beamlet laser chamber to spectroscopically study laser produced plasmas from different material targets.

Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1976 with total page 1292 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book ERDA Energy Research Abstracts written by United States. Energy Research and Development Administration and published by . This book was released on 1977 with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the 2nd International Conference on Radiative Properties of Hot Dense Matter Sarasota Florida Oct 31 NOv 4 1983 written by Jack Davis and published by . This book was released on 1985 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fusion Energy Update written by and published by . This book was released on 1979 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Atomic Physics in Hot Plasmas written by David Salzmann and published by Oxford University Press. This book was released on 1998-08-20 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to provide the reader with a coherent and updated comprehensive treatise that covers the central subjects of the field. The style and content is suitable both for students and researchers. Highlights of the book include (among many others) the Ion-Sphere model, statistical models, Average-Atom model, emission spectrum, unresolved transition arrays, supertransition arrays, radiation transport, escape factors and x-ray lasers.

Download or read book Advances in Atomic and Molecular Physics written by and published by Academic Press. This book was released on 1981-08-17 with total page 403 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Atomic and Molecular Physics

Download or read book Radiative Processes in Discharge Plasmas written by Joseph M. Proud and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: An Advanced Study Institute on Radiative Processes in Discharge Plasmas was held at the Atholl Palace Hotel, Pitlochry, Perthshire, Scotland, June 23 through July 5, 1985. This publication is the Pro ceedings from that Institute. The Institute was attended by eighty-five Participants and Lecturers representing the United States, Canada, France, West Germany, Greece, The Netherlands, Portugal, Turkey, the United Kingdom, and Switzerland. A distinguished faculty of eighteen Lecturers was assembled and the topical program organized with the assistance of an Advisory Committee composed of: Dr. John Waymouth, USA; Dr. Timm Teich, Switzerland; Dr. Arthur Phelps, USA; Dr. Nicol Peacock, England; Professor Erich Kunhardt, USA; Dr. Anthony Hyder, USA; and Dr. Arthur Guenther, USA. The underlying theme and objective of the Institute was the enhance ment of scientific communication and exchange among academic, industrial, and national laboratory groups having a common concern for radiative processes in discharge plasmas. The program was organized into four major sessions sequentially treating: the fundamental science of visible and near-visible radiation in plasmas; the technology of discharge light sources; recent and novel methods for the generation of plasmas; and an update on advances in laser-based diagnostics. Each major session culmi nated in a panel discussion comprised of the Lecturers for that session.

Download or read book Space and Time Resolved Spectroscopy of Laser produced Plasmas written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The determination of level populations and detailed population mechanisms in dense plasmas has become an increasingly important problem in atomic physics. In this work, the density variation of line intensities and level populations in aluminum K-shell and molybdenum and silver L-shell emission spectra have been measured from high-powered, laser-produced plasmas. For each case, the density dependence of the observed line emission is due to the effect of high frequency electron-ion collisions on metastable levels. The density dependent line intensities vary greatly in laser-produced plasmas and can be used to extract detailed information concerning the population kinetics and level populations of the ions. The laser-plasmas had to be fully characterized in order to clearly compare the observed density dependence with atomic theory predictions. This has been achieved through the combined use of new diagnostic instruments and microdot targets which provided simultaneously space, time, and spectrally resolved data. The plasma temperatures were determined from the slope of the hydrogen-like recombination continuum. The time resolved electron density profiles were measured using multiple frame holographic interferometry. Thus, the density dependence of K-shell spectral lines could be clearly examined, independent of assumptions concerning the dynamics of the plasma. In aluminum, the electron density dependence of various helium-like line intensity ratios were measured. Standard collisional radiative equilibrium models fail to account for the observed density dependence measured for the ''He/sub .cap alpha.//IC'' ratio. Instead, a quasi-steady state atomic model based on a purely recombining plasma is shown to accurately predict the measured density dependence. This same recombining plasma calculation successfully models the density dependence of the high-n ''He/sub .gamma.//He/sub .beta./'' and ''He/sub delta//He/sub .beta./'' helium-like resonance line intensity ratios.

Download or read book Physics Briefs written by and published by . This book was released on 1992 with total page 864 pages. Available in PDF, EPUB and Kindle. Book excerpt: