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AbstractAbstract
[en] A model for ion-atom collisions at intermediate energies is proposed in which the conventional close-coupled approach and the eikonal theory of Glauber are unified. The results are presented for direct H(1s) → H(2s) excitation by proton impact in a two-channel formalism. The conditions under which the model becomes applicable to electron-atom scattering are also examined. (author)
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Journal Article
Journal
Journal of Physics. B, Atomic and Molecular Physics; ISSN 0022-3700;
; v. 11(2); p. L37-L41

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ATOM COLLISIONS, BARYONS, CATIONS, CHARGED PARTICLES, COLLISIONS, ELECTRON COLLISIONS, ELEMENTARY PARTICLES, ELEMENTS, ENERGY RANGE, ENERGY-LEVEL TRANSITIONS, FERMIONS, HADRONS, HYDROGEN IONS, HYDROGEN IONS 1 PLUS, ION COLLISIONS, IONS, KEV RANGE, MATHEMATICAL MODELS, NONMETALS, NUCLEONS, SCATTERING
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AbstractAbstract
[en] Conditions of the experiments are considered for observation of parity nonconservation in radiative atomic transitions in the case of hydrogen - like atoms and two-electron ions. Calculations are carried out for H, He C+3 and Cu +27 limitations on a beam and residual gass density, external magnetic and electric fields are calculated. The time of the experiment is also estimated. The conditions appear to be really practible only in the case of Cu+27
Original Title
Ob effektakh, prepyatstvuyushchikh nablyudeniyu nesokhraneniya chetnosti v vodorodopodobnykh i geliepodobnykh ionakh
Primary Subject
Source
For English translation see the journal Sov. Phys. - JETP.
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Journal Article
Journal
Zhurnal Ehksperimental'noj i Teoreticheskoj Fiziki; v. 73(1); p. 122-127
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[en] Shanks' (J. Math. Phys.; 34:1 (1955)) generalisation of Aitken's delta2 transformation is presented as a ratio of persymmetric determinants, and an algorithm for calculating these is given. The superiority of the generalised transformation over repeated delta2 transformations for summing perturbation series is shown. (author)
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Journal Article
Journal
Journal of Physics. B, Atomic and Molecular Physics; ISSN 0022-3700;
; v. 11(2); p. L31-L35

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AbstractAbstract
[en] Simple expressions are given relating linear and circular polarization of radiation, emitted following collisions of electrons with atoms, to Fano-Macek orientation and alignment parameters (Rev. Mod. Phys. 45: 553 (1973)). The p→s and d→p cases are considered explicitly, with and without unresolved fine structure. Several errors in the literature are corrected. Results are given for Lyα at 100 eV. (14 references) (author)
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Journal Article
Journal
Comments on Atomic and Molecular Physics; ISSN 0010-2687;
; v. 7(5-6); p. 123-128

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AbstractAbstract
[en] The lifetimes of some levels of the 4d55p and 4d45s5p configurations have been determined by zero-field level-crossing technique. The results are: 4d55p: tau(7P4) = 14.4(8) ns; tau(7P3) = 15.8(8) ns; tau(7P2) = 13.6(7) ns. 4d45s5p: tau(7P4) = 5.7(6) ns; tau(7P3) = 10.2(5) ns; tau(7P2) = 6.0(5) ns; tau(7D3) = 12.1(10) ns; tau(7D2) = 8.2(8) ns. (Auth.)
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Journal Article
Journal
Physics Letters. A; ISSN 0375-9601;
; v. 68(3-4); p. 319-320

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[en] Ionisation of atomic systems by fast ions is considered. A second-order quantum theory is derived which correctly accounts for all distortions of the initial- and final-state wavefunctions arising from Coulomb interactions between three charged particles. The present transition amplitude is the rigorous first order (or lowest order) approximation to the exact scattering amplitude for ionisation treated by the Faddeev equations in the distorted wave formalism. The problem is briefly studied by the impact parameter method as well, and its equivalence with the full quantal treatment is proved (for projectiles mainly scattered forward) in the limit of very large valUes of the reduced mass. As an illustration of the present theory, ionisation of atomic hydrogen by proton impact is examined at incident energies between 25 and 200 keV. Comprehensive comparisons of available experimental data with singly differential as well as total cross sections for electron ejection are made and the validity of the present method is assessed. (author)
Primary Subject
Record Type
Journal Article
Journal
Journal of Physics. B, Atomic and Molecular Physics; ISSN 0022-3700;
; v. 11(20); p. 3529-3552

Country of publication
COMPARATIVE EVALUATIONS, COULOMB FIELD, DIFFERENTIAL CROSS SECTIONS, DISTORTED WAVE THEORY, ELECTRON EMISSION, ELECTRON SPECTRA, FADDEEV EQUATIONS, HYDROGEN, IMPACT PARAMETER, ION-ATOM COLLISIONS, IONIZATION, KEV RANGE 100-1000, KEV RANGE 10-100, PROTON REACTIONS, QUANTUM FIELD THEORY, SCATTERING AMPLITUDES, TOTAL CROSS SECTIONS, TRANSITION AMPLITUDES, WAVE FUNCTIONS
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[en] The energies and widths of the lowest 1P0 and the second 1S resonance below the n=2 threshold in H- have been determined by a scattering calculation employing the algebraic variational method. (Auth.)
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Journal Article
Journal
Physics Letters. A; ISSN 0375-9601;
; v. 68(3-4); p. 315-316

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AbstractAbstract
No abstract available
Original Title
Rasseyanie nizkoehnergetichnykh ehlektronov na molekulakh CO
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Source
Short note; for English translation see the journal Sov. J. Plasma Phys.
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Journal Article
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Fizika Plazmy; v. 4(4); p. 941-942
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[en] As part of a kinetic study of XeF laser media, we have followed the time evolution of the Ne*, F*, and F*2 densities in e-beam excited Ne/Xe/NF3(F2) mixtures. The Ne* and F* densities were monitored by laser absorption while the F2* was observed in emission at 158 nm. Rate coefficients for the quenching of these excited states by Ne, Xe, NF3, and F2 have been determined. The radiative lifetime of the F2* was measured to be 41 +- 4 x 10-9 sec
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Journal Article
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Journal of Chemical Physics; v. 69(11); p. 5133-5139
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[en] The recent discovery by Khare that choosing the CS partial wave parameter l-bar to be the initial orbital angular momentum, l/sub i/, leads to a simple differential scattering amplitude for definite polarization transitions is examined in detail. It is found that the resulting scattering amplitude formula, which is a rotation of the usual McGuire--Kouri formula, predicts nonzero magnetic transitions in all frames except that whose Z axis always points in the final observation direction R. A detailed comparison of l/sub i/ and l/sub f/ labeling is made and it is shown that both lead to nondiagonal approximations to the p-helicity amplitude, T/sup J/(jlambdavertical-barj0m0), and to differential scattering amplitudes which have the proper limiting behavior at small and large scattering angles. In addition it is shown that both l/sub i/ and l/sub f/ labeling yield identical results for all degeneracy averaged cross sections, including the general relaxation cross sections. Further, we show rigorously that if the quantization axis is along a direction perpendicular to the plane of the incident and final momenta, then the l/sub i/ and l/sub f/ labeled cross sections are identical. It is argued on the basis of available numerical results and on physical grounds that the l/sub i/-labeled CS is preferred over the l/sub f/ CS for calculating magnetic transitions quantized along the incident momentum. We further expect the l/sub f/ CS to be preferred for calculating magnetic transitions quantized along the final momentum. However, other l-bar choices may be better yet for magnetic transitions in general
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Journal Article
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Journal of Chemical Physics; v. 69(10); p. 4419-4430
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