Download or read book Improving Calculations of the Interaction Between Atoms and Plasma Particles and Its Effect on Spectral Line Shapes written by Thomas Alexander Gomez and published by . This book was released on 2017 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectral line broadening has many applications in astrophysics and plasma physics. Calculations of line broadening are used in nearly all opacity models, which are then folded into atmosphere or radiative-transfer models, or used as density diagnostics in laboratory plasmas. However, there is evidence to suggest that spectral models are incomplete. For example, the experiment designed to measure the iron opacity at solar interior conditions has revealed significant discrepancies between measured and modeled opacities. Additionally, the determination of masses in white dwarfs using spectroscopic methods does not agree with other opacity-model-independent methods. Due to the challenging nature of line-broadening calculations, approximations are often employed in order to keep the calculation tractable. One approximation that will be examined in this thesis is how charged plasma particles (electrons, ions, and atoms) are assumed to interact with each other. These charged plasma particles interact via a Coulomb potential; in low-density plasmas, this can be approximated by a second-order Taylor expansion, and the plasma particles are assumed to be always outside the radiator (dipole approximation). The dipole approximation is used extensively throughout spectral line-broadening calculations---even beyond its validity criteria. In this dissertation, I am improving the treatment of the interaction between the radiator and the plasma particles for close interactions and will focus on an accurate treatment of penetrating collisions of plasma particles with the radiator. The first improvement is to examine when the higher-order Taylor terms become important and when the dipole-only approximation breaks down. I further explore the effects of penetrating collisions due to electrons and ions. At extremely high densities, the wave behavior of quantum electrons starts to become important. As a first test of the quantum theory of electron collisions with penetration, I attempted to create correspondence between the new quantum calculation and semi-classical calculations in a regime where quantum effects aren't important. However, I could not create correspondence without the Pauli exclusion (which has been neglected in previous calculations): since electrons exist in both the plasma and the atom, the quantum repulsion of electrons (due to being spin-1/2 particles) needed to be included explicitly. There are also additional terms present in the broadening operator which have been previously neglected and considered for the first time here. I also explore the effect of penetrating collisions due to ions, for it is this treatment that is important for calculations of line merging and continuum lowering (sometimes called ionization potential depression)---a hotly debated physical effect. While I include many improvements in this thesis, it is in no way complete; there are many other untested effects that are commonly used in spectral-line broadening calculations. I conclude by showing some of the astrophysical implications specifically to white dwarfs.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1975 with total page 1146 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectral Line Broadening by Plasmas written by Hans Griem and published by Elsevier. This book was released on 2012-12-02 with total page 425 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectral Line Broadening by Plasmas deals with spectral line broadening by plasmas and covers topics ranging from quasi-static approximation and impact approximation to intermediate approximations and correlation effects. Experimental results for hydrogen lines, lines with forbidden components, and ionized helium lines are presented. Applications such as density and temperature measurements are also considered. Comprised of four chapters, this volume begins with an overview of the effects of electric fields from electrons and ions (both acting as point charges) on spectral line shapes. The next chapter surveys theoretical work, paying particular attention to quasi-static, impact, and intermediate approximations as well as correlation effects. Stark broadening experiments are then discussed, with special emphasis on experiments capable of checking the accuracy or validity limits of the various approximations. The final chapter is devoted to applications in laboratory plasma physics and astronomy, focusing on density and temperature measurements and opacity calculations as well as the analysis of stellar atmospheres, amplitudes and spectra of plasma waves, and radio frequency lines. This book should appeal to students, practitioners, and researchers in pure and applied physics.
Download or read book Stark Broadening of Spectral Lines in Plasmas written by Eugene Oks and published by MDPI. This book was released on 2019-01-14 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Stark Broadening of Spectral Lines in Plasmas" that was published in Atoms
Download or read book Spectral Line Shapes in Astrophysics and Related Topics written by Milan S. Dimitrijević and published by MDPI. This book was released on 2020-02-18 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectral lines, widths, and shapes are powerful tools for emitting/absorbing gas diagnostics in different astrophysical objects (from the solar system to the most distant objects in the universe—quasars). On the other hand, experimental and theoretical investigations of laboratory plasma have been applied in spectroscopic astrophysical research, especially in research on atomic data needed for line shape calculations. Data on spectral lines and their profiles are also important for diagnostics, analysis, and the modelling of fusion plasma, laser-produced plasma, laser design and development, and various plasmas in industry and technology, like light sources based on plasmas or the welding and piercing of metals by laser-produced plasma. The papers from this book can be divided into four groups: 1. stark broadening data for astrophysical and laboratory plasma investigations; 2. applications of spectral lines for astrophysical and laboratory plasma research; 3. spectral line phenomena in extragalactic objects, and 4. laboratory astrophysics results for spectra investigation. The reviews and research papers, representing new research on the topics presented in this book, are of interest for specialists and PhD students. We hope that the present book will be useful and interesting for scientists interested in the investigation of spectral line shapes and will contribute to the education of young researchers and PhD students.
Download or read book Quantum Statistics of Charged Particle Systems written by W.D. Kraeft and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: The year 1985 represents a special anniversary for people dealing with Ooulomb systems. 200 years ago, in 1785, Oharles Auguste de Ooulomb (1736-1806) found "Ooulomb's law" for the interaction force between charged particles. The authors want to dedicate this book to the honour of the great pioneer of electrophysics. Recent statistical mechanics is mainly restricted to systems of neutral particles. Except for a few monographs and survey articles (see, e. g., IOHIMARU, 1973, 1982; KUDRIN, 1974; KLIMONTOVIOH, 1975; EBELING, KRAEFT and KREMP, 1976, 1979; KALMAN and CARINI, 1978; BAUS and HANSEN, 1980; GILL, 1981, VELO and WIGHT MAN, 1981; MATSUBARA, 1982) the extended material on charged particle systems, which is now available thanks to the efforts of many workers in statistical mechanics, is widely dispersed in many original articles. It is the aim of this monograph to represent at least some part of the known results on charged particle systems from a unified point of view. Here the method of Green's functions turns out to be a powerful method especially to overcome the difficulties connected with the statistical physics of charged particle systems; some of them are . mentioned in the introduction. Here we can point, e.g., to the appearance of bound states in a medium and their role as new entities.
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1972 with total page 628 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications written by United States. National Bureau of Standards and published by . This book was released on 1991 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Physics written by Andreas Dinklage and published by Springer Science & Business Media. This book was released on 2005-06-09 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma Physics: Confinement, Transport and Collective Effects provides an overview of modern plasma research with special focus on confinement and related issues. Beginning with a broad introduction, the book leads graduate students and researchers – also those from related fields - to an understanding of the state-of-the-art in modern plasma physics. Furthermore, it presents a methodological cross section ranging from plasma applications and plasma diagnostics to numerical simulations, the latter providing an increasingly important link between theory and experiment. Effective references guide the reader from introductory texts through to contemporary research. Some related exercises in computational plasma physics are supplied on a special web site
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1993 with total page 556 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book OAR Cumulative Index of Research Results written by and published by . This book was released on with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Publications of the National Institute of Standards and Technology Catalog written by National Institute of Standards and Technology (U.S.) and published by . This book was released on 1991 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Zeitschrift F r Naturforschung written by and published by . This book was released on 1995 with total page 650 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 1994-10 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook Of Radiative Heat Transfer In High Temperature Gase written by R I Soloukhin and published by CRC Press. This book was released on 2000-07-20 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt: Very Good,No Highlights or Markup,all pages are intact.
Download or read book Optics and Spectroscopy written by and published by . This book was released on 1994 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1987 with total page 1014 pages. Available in PDF, EPUB and Kindle. Book excerpt:
