Electron Elastic Scattering Resonances in the Collision of Fast Hydrogenic Ions with Molecular Hydrogen

A scattering process can be a natural process or a process carried out in a laboratory. The scattering of particles from targets has resulted in important discoveries in physics. We discuss various scattering theories of electrons and positrons and their applications to elastic scattering, resonances, photoabsorption, excitation, and solar and stellar atmospheres. Among the most commonly employed approaches are the Kohn variational principle, close-coupling approximation, method of polarized orbitals, R-matrix formulation, and hybrid theory. In every formulation, an attempt is made to include exchange, long-range and short-range correlations, and to make the approach variationally correct. The present formulation, namely, hybrid theory, which is discussed in greater detail compared to other approximations, includes exchange, long-range correlations, and short-range correlations at the same time, and is variationally correct. It was applied to calculate the phase shifts for elastic scattering, the resonance parameters of two-electron systems, photoabsorption in two-electron systems, excitation of atomic hydrogen by an electron and positron impact, and to study the opacity of the Sun’s atmosphere. Calculations of polarizabilities, Rydberg states, and bound states of atoms are also discussed.

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Suppression of elastic scattering resonances in microdroplets seeded with nm-sized latex particles

10.1117/12.145699 ◽

1993 ◽

Author(s):

Dat D. Ngo ◽

Ronald G. Pinnick

Keyword(s):

Elastic Scattering ◽

Latex Particles ◽

Scattering Resonances

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The collision of electrons with molecules

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1932.0033 ◽

1932 ◽

Vol 135 (826) ◽

pp. 258-275 ◽

Cited By ~ 45

Keyword(s):

Elastic Scattering ◽

Electron Impact ◽

Molecular Hydrogen ◽

Electron Exchange ◽

Collision Theory ◽

Considerable Detail

Since the development of the Born theory of collisions in 1926, its application to collisions of electrons with atoms has been treated in considerable detail. Recently the authors have included also the modification due to Oppenheimer, in which account is taken of electron exchange. However, for the collision of electrons with molecules very little has been done beyond the calculation by Massey of the elastic scattering of electrons in molecular hydrogen. In the present paper use is made of the collision theory of Born and of Oppenheimer ( loc. cit .) in order to consider various phenomena occurring on electron impact with molecules.

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Parity mixing of elastic scattering resonances: General theory and application toN14

Physical Review C ◽

10.1103/physrevc.30.456 ◽

1984 ◽

Vol 30 (2) ◽

pp. 456-463 ◽

Cited By ~ 16

Author(s):

E. G. Adelberger ◽

P. Hoodbhoy ◽

B. A. Brown

Keyword(s):

Elastic Scattering ◽

General Theory ◽

Scattering Resonances

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Angular distributions in the elastic scattering and rotational excitation of molecular hydrogen by atomic hydrogen

The Astrophysical Journal ◽

10.1086/153731 ◽

1975 ◽

Vol 199 ◽

pp. 637 ◽

Cited By ~ 15

Author(s):

S.-I. Chu ◽

A. Dalgarno

Keyword(s):

Elastic Scattering ◽

Atomic Hydrogen ◽

Molecular Hydrogen ◽

Angular Distributions ◽

Rotational Excitation

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Theory of the elastic scattering of electrons in molecular hydrogen

Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character ◽

10.1098/rspa.1930.0178 ◽

1930 ◽

Vol 129 (811) ◽

pp. 616-627 ◽

Cited By ~ 12

Keyword(s):

Elastic Scattering ◽

Cross Sections ◽

Atomic Hydrogen ◽

Molecular Hydrogen ◽

Hydrogen Molecule ◽

Incident Beam ◽

Quantum Mechanical ◽

Experimental Conditions ◽

Actual Case ◽

Mechanical Methods

Since tbe introduction of quantum mechanical methods, the theory of scattering of electrons by atoms and ions has been developed very considerably. In the case of elastic collisions it is possible to determine the effective cross sections presented by atoms to a beam of electrons, from a knowledge of the potential in the atom. This has been done for helium by Mott and the calculated cross sections agree well with the experimental. Unfortunately, the simplest theoretical case, that of the elastic scattering of electrons by atomic hydrogen, the theory of which has been given by Elsasser, is extremely difficult to attain experimentally, 50 to 60 per cent, atomic hydrogen being the maximum at present attainable. It thus would seem of interest to consider what effects would be expected by using molecular instead of atomic hydrogem This case is also novel in that we are considering an axially symmetrical field and the number of electrons scattered through a given angle depends on the orientation of the axis relative to the initial and final beams. In an actual case the axes of the molecules may be taken as in random directions, the hydrogen molecule having no permanent dipole moment and so being only slightly oriented by the electric field of the incident beam. This permits us to average the scattering over all orientation to obtain experimental conditions.

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