Results 251 to 260 of about 6,243,018 (311)
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Atomic photoabsorption cross sections
Journal of Quantitative Spectroscopy and Radiative Transfer, 1967Abstract Results are reported of extensive calculations on atomic photoabsorption cross sections by the statistical method in various approximations, based on developments presented in previous papers. A closely spaced family of photoabsorption cross sections emerges which, on scaling with regard to atomic numbers, represents in an unified manner the
Werner Brandt +2 more
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Cross sections for the alkali atom-Br2 reactions
The Journal of Chemical Physics, 1973The reaction cross sections of alkali metal atoms with bromine molecules have been obtained by direct measurements of alkali atom decay rates. The alkali atoms were produced in the presence of a known amount of bromine molecules by photodissociating the bromide of the particular alkali atom with a short pulse of uv light.
J. Maya, P. Davidovits
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Cross sections for electron scattering by atomic potassium
Physical Review A, 1992Electron elastic and collisional excitation cross sections from the ground state of potassium are calculated using the noniterative integral-equation method of Henry, Rountree, and Smith [Comput. Phys. Commun. 23, 233 (1981)] in the electron energy range 4\ensuremath{\le}E\ensuremath{\le}200 eV. Configuration-interaction target wave functions that take
, Msezane, , Awuah, , Hiamang, , Allotey
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Nature of the dips in the atomic photoabsorption cross section
Physical Review A, 1992It is shown that the appearance of the plateau on the atomic electron density n(r) gives rise to the dip in the photoabsorption cross section of a many-electron atom. The dip at frequency ω is formed if (a) there is a point of plasma resonance r 0 where the local plasma frequency inside the atom is equal to ω, and (b) the derivative of electron ...
, Tolstikhin, , Vinogradov
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Stopping cross-sections and atomic potentials
Radiation Effects, 1976Abstract A strong correlation is shown to exist throughout the periodic table : etween the Z 2 dependence of the electronic stopping cross-sections for 4He ions of a given velocity and the Z dependence of the atomic potentials at a certain radius. An empirical formula is presented which allows the extrapolation of stopping cross-section data for any ...
J. C. Eckardt +2 more
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Elastic cross sections of hydrogen atoms
Proceedings of the Physical Society, 1967Differential and total elastic cross sections for the collision of unpolarized beams of hydrogen atoms have been evaluated for energies of the relative motion up to 0 37 ev (ka0 = 5). The cross sections have been calculated from accurate phase shifts derived from numerical integration of the radial wave equations using the interaction potentials of ...
J W Fox, E Gal
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Photoionization cross sections of atomic ions
Journal of Electron Spectroscopy and Related Phenomena, 2002Abstract Experimental techniques for photoionisation measurements on atomic ions are described, and recent progress in the measurement of absolute photoionisation cross sections is reviewed. The complementary contributions of the two main experimental methods, merged beam and dual laser produced plasma (DLPP), pointing out both the problems and ...
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Maximum Ionization Cross Section of Atoms
The Journal of Chemical Physics, 1969Various theoretical approaches for estimation of maximum ionization cross sections have been discussed and three new relations have been developed and used to evaluate maximum cross sections. Mann's calculations have been critically examined, and the present results have been compared with available experimental results.
Prabhakar Tiwari +2 more
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On atomic photoionization cross section calculation
Physics Letters A, 1969Abstract Essential peculiarities of the Hartree-Fock photoionization cross section are discussed: 1) the choice of the operator of interaction with the electromagnetic field, 2) sum rules and 3) the influence of various modifications of the self-consistent field.
M.Ya. Amusia +3 more
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Electron Ionization Cross Sections for Atomic Subshells
Microscopy and Microanalysis, 2003Ionization of atoms is the first step in many analytical procedures. The cross section for ionizing a particular atomic shell is essential for calculating the magnitude of analytical signals. Calculations using atomic wave functions for various shells of all elements relevant for X-ray microanalysis over a range of electron energies up to 400 keV ...
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