scispace - formally typeset
Search or ask a question
Author

Oleg Zatsarinny

Other affiliations: Western Michigan University
Bio: Oleg Zatsarinny is an academic researcher from Drake University. The author has contributed to research in topics: Ionization & Excited state. The author has an hindex of 34, co-authored 205 publications receiving 4135 citations. Previous affiliations of Oleg Zatsarinny include Western Michigan University.


Papers
More filters
Journal ArticleDOI
Oleg Zatsarinny1
TL;DR: BSR is a general program to calculate atomic continuum processes using the B-spline R-matrix method, including electron–atom and electron–ion collision processes, and radiative processes such as bound–bound transitions, photoionization and polarizabilities.

240 citations

Journal ArticleDOI
TL;DR: In this paper, a comprehensive dielectronic recombination database within the generalized collisional-radiative (GCR) framework is presented, which is valid for modeling ions of elements in dynamic finite-density plasmas such as occur in transient solar flares and in the divertors and high transport regions of magnetic fusion devices.
Abstract: A programme is outlined for the assembly of a comprehensive dielectronic recombination database within the generalized collisional-radiative (GCR) framework. It is valid for modelling ions of elements in dynamic finite-density plasmas such as occur in transient astrophysical plasmas such as solar flares and in the divertors and high transport regions of magnetic fusion devices. The resolution and precision of the data are tuned to spectral analysis and so are sufficient for prediction of the dielectronic recombination contributions to individual spectral line emissivities. The fundamental data are structured according to the format prescriptions of the Atomic Data and Analysis Structure (ADAS) and the production of relevant GCR derived data for application is described and implemented following ADAS. The requirements on the dielectronic recombination database are reviewed and the new data are placed in context and evaluated with respect to older and more approximate treatments. Illustrative results validate the new high-resolution zero-density dielectronic recombination data in comparison with measurements made in heavy-ion storage rings utilizing an electron cooler. We also exemplify the role of the dielectronic data on GCR coefficient behaviour for some representative light and medium weight elements.

226 citations

Journal ArticleDOI
TL;DR: LXCat as mentioned in this paper is an open-access platform for curating data needed for modeling the electron and ion components of technological plasmas, including scattering cross sections and swarm/transport parameters, ion-neutral interaction potentials, and optical oscillator strengths.
Abstract: LXCat is an open-access platform (www.lxcat.net) for curating data needed for modeling the electron and ion components of technological plasmas. The data types presently supported on LXCat are scattering cross sections and swarm/transport parameters, ion-neutral interaction potentials, and optical oscillator strengths. Twenty-four databases contributed by different groups around the world can be accessed on LXCat. New contributors are welcome; the database contributors retain ownership and are responsible for the contents and maintenance of the individual databases. This article summarizes the present status of the project.

177 citations

Journal ArticleDOI
TL;DR: In this article, the basic ideas of the B-spline R-matrix approach are reviewed, and the use of the method is illustrated with a variety of applications to atomic structure, electron?atom collisions and photo-induced processes.
Abstract: The basic ideas of the B-spline R-matrix (BSR) approach are reviewed, and the use of the method is illustrated with a variety of applications to atomic structure, electron?atom collisions and photo-induced processes. Special emphasis is placed on complex, open-shell targets, for which the method has proven very successful in reproducing, for example, a wealth of near-threshold resonance structures. Recent extensions to a fully relativistic framework and intermediate energies have allowed for an accurate treatment of heavy targets as well as a fully nonperturbative scheme for electron-impact ionization. Finally, field-free BSR Hamiltonian and electric dipole matrices can be employed in the time-dependent treatment of intense short-pulse laser?atom interactions.

168 citations

Journal ArticleDOI
TL;DR: In this paper, the B-spline Breit-Pauli R-matrix method was used to estimate the collision strengths for the astrophysically important lines in S II and the effective collision strengths were obtained by averaging the electron collision strengths over a Maxwellian distribution of velocities.
Abstract: New improved calculations are reported for transition probabilities and electron impact excitation collision strengths for the astrophysically important lines in S II. The collision strengths have been calculated in the close-coupling approximation using the B-spline Breit-Pauli R-matrix method. The multiconfiguration Hartree-Fock method with term-dependent non-orthogonal orbitals is employed for an accurate representation of the target wave functions. The close-coupling expansion includes 70 bound levels of S II covering all possible terms of the ground 3s 23p 3 and singly excited 3s3p 4, 3s 23p 23d, 3s 23p 24s, and 3s 23p 24p configurations. The present calculations are more extensive than previous ones, leading to a total 2415 transitions between fine-structure levels. The effective collision strengths are obtained by averaging the electron collision strengths over a Maxwellian distribution of velocities and these are tabulated for all fine-structure transitions at electron temperatures in the range from 5000 to 100,000 K. The present results are compared with a variety of other close-coupling calculations and available experimental data. There is an overall good agreement with the recent 18-state calculations by Ramsbottom, Bell, & Stafford and with the 19-state calculations by Tayal for the most part, but some significant differences are also noted for some transitions.

140 citations


Cited by
More filters
Journal Article
TL;DR: In this paper, the subject of quantum electrodynamics is presented in a new form, which may be dealt with in two ways: using redundant variables and using a direct physical interpretation.
Abstract: THE subject of quantum electrodynamics is extremely difficult, even for the case of a single electron. The usual method of solving the corresponding wave equation leads to divergent integrals. To avoid these, Prof. P. A. M. Dirac* uses the method of redundant variables. This does not abolish the difficulty, but presents it in a new form, which may be dealt with in two ways. The first of these needs only comparatively simple mathematics and is directly connected with an elegant general scheme, but unfortunately its wave functions apply only to a hypothetical world and so its physical interpretation is indirect. The second way has the advantage of a direct physical interpretation, but the mathematics is so complicated that it has not yet been solved even for what appears to be the simplest possible case. Both methods seem worth further study, failing the discovery of a third which would combine the advantages of both.

1,398 citations

Book
09 Jan 2011
TL;DR: In this paper, a comprehensive and richly illustrated textbook on the astrophysics of the interstellar and intergalactic medium is presented, including the gas and dust, as well as the electromagnetic radiation, cosmic rays, and magnetic and gravitational fields, present between the stars in a galaxy and also between galaxies themselves.
Abstract: This is a comprehensive and richly illustrated textbook on the astrophysics of the interstellar and intergalactic medium--the gas and dust, as well as the electromagnetic radiation, cosmic rays, and magnetic and gravitational fields, present between the stars in a galaxy and also between galaxies themselves. Topics include radiative processes across the electromagnetic spectrum; radiative transfer; ionization; heating and cooling; astrochemistry; interstellar dust; fluid dynamics, including ionization fronts and shock waves; cosmic rays; distribution and evolution of the interstellar medium; and star formation. While it is assumed that the reader has a background in undergraduate-level physics, including some prior exposure to atomic and molecular physics, statistical mechanics, and electromagnetism, the first six chapters of the book include a review of the basic physics that is used in later chapters. This graduate-level textbook includes references for further reading, and serves as an invaluable resource for working astrophysicists. * Essential textbook on the physics of the interstellar and intergalactic medium * Based on a course taught by the author for more than twenty years at Princeton University * Covers radiative processes, fluid dynamics, cosmic rays, astrochemistry, interstellar dust, and more * Discusses the physical state and distribution of the ionized, atomic, and molecular phases of the interstellar medium * Reviews diagnostics using emission and absorption lines * Features color illustrations and detailed reference materials in appendices * Instructor's manual with problems and solutions (available only to teachers)

1,143 citations

Journal ArticleDOI
TL;DR: In this paper, a list of atomic data for the lighter elements from hydrogen to gallium is presented, with a focus on resonance lines, i.e., lines whose lower level is the ground state, or an excited fine-structure state of the ground term, and restricted to wavelengths longward of the H I Lyman limit at 911.753?.
Abstract: This compilation revises the 1991 listing of atomic data for the lighter elements from hydrogen to gallium. The tabulation emphasizes resonance lines, i.e., lines whose lower level is the ground state, or an excited fine-structure state of the ground term, and is restricted to wavelengths longward of the H I Lyman limit at 911.753 ?. All but the very weakest known and predicted electric-dipole transitions are included, but no forbidden lines. This paper has attempted to review all data published by the end of 2002.?????The tables contain the best data available to the author on ionization potentials, level designations, vacuum and air wavelengths, lower and upper energy levels, statistical weights, transition probabilities, natural damping constants (reciprocal lifetimes), oscillator strengths, and the often used combinations of log gf and log ?f. All ion stages with relevant classified lines are included. Individual components resulting from isotope shift and hyperfine structure are listed explicitly for certain species. The accompanying text provides references, explanations for the critical selection of data, and notes indicating where new measurements or calculations are needed.?????This compilation should be particularly useful in the analysis of interstellar and quasar absorption lines and other astrophysical sites where the density of particles and radiation is low enough to excite only the lowest atomic levels. The data also are relevant to the study of stellar atmospheres, and gaseous nebulae.?????An Appendix summarizes new data relevant to the similar compilation in Paper II for the elements germanium to uranium.

806 citations

Journal ArticleDOI
01 Aug 1952-Nature
TL;DR: Lang as discussed by the authors reviewed Lang's work in the Journal of Scientific Instruments (JSI) and Supplement No 1, 1951 Pp xvi + 388 + iii + 80 (London: Institute of Physics, 1951).
Abstract: Journal of Scientific Instruments Editor: Dr H R Lang Vol 28 and Supplement No 1, 1951 Pp xvi + 388 + iii + 80 (London: Institute of Physics, 1951) Bound, £3 12s; unbound, £3

725 citations