Scattering of intermediate-energy positrons by C, N, O atoms and the corresponding diatomic molecules: elastic and total cross-sections

A brief survey of available theoretical techniques is given for positron–atom scattering. The distinction between methods involving a finite number of target states and those with an infinite number of target states is emphasized. The situation regarding total cross sections is summarized, and a new, non-perturbative, eikonal-type approximation, based on the work of Wallace, is introduced.

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A semi-empirical formula for total cross sections of electron scattering from diatomic molecules

Physics Letters A ◽

10.1016/0375-9601(96)00638-x ◽

1996 ◽

Vol 222 (4) ◽

pp. 233-236 ◽

Cited By ~ 7

Author(s):

Yufang Liu ◽

Jinfeng Sun

Keyword(s):

Electron Scattering ◽

Cross Sections ◽

Empirical Formula ◽

Diatomic Molecules ◽

Total Cross Sections ◽

Semi Empirical

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Thermal scattering of atoms by homonuclear diatomic molecules

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1963.0142 ◽

1963 ◽

Vol 274 (1359) ◽

pp. 427-442 ◽

Cited By ~ 197

Keyword(s):

Cross Sections ◽

Diatomic Molecules ◽

Rotational Quantum Number ◽

Formal Theory ◽

Rotational Transition ◽

Rigid Rotator ◽

Total Cross Sections ◽

Total Scattering Cross Section ◽

Scattering Of Atoms ◽

Homonuclear Diatomic Molecules

The formal theory of scattering by a rigid rotator is applied to the problem of the rotational excitation and elastic scattering of homonuclear diatomic molecules by atoms. A statistical theory is employed to analyze the effects of the strong coupling which occurs between the different scattering channels. According to this theory the Massey-Mohr formula provides a good approximation to the total scattering cross-section, an upper limit of ½ holds for the ratio of inelastic to total cross-sections and the probability of a rotational transition does not depend very sensitively on the corresponding change in the rotational quantum number. Numerical results are presented for the collision of argon and nitrogen at room temperature.

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GENETIC PROGRAMMING APPROACH FOR ELECTRON-ALKALI-METAL ATOM COLLISIONS

International Journal of Modern Physics B ◽

10.1142/s0217979206035825 ◽

2006 ◽

Vol 20 (32) ◽

pp. 5463-5471 ◽

Cited By ~ 4

Author(s):

SALAH YASEEN EL-BAKRY ◽

AMR RADI

Keyword(s):

Experimental Data ◽

Genetic Programming ◽

Cross Sections ◽

Alkali Metal Atom ◽

Intermediate Energy ◽

Target Atom ◽

Programming Approach ◽

Dipole Polarizability ◽

Total Cross Sections ◽

Alkali Atoms

New technique is presented for modeling the total cross sections of electron scattering by Na, K, Rb and Cs atoms in the low and intermediate energy regions. The calculations have been performed in the framework of genetic programming (GP) technique. The GP has been running based on the experimental data of the total collisional cross sections to produce the total cross sections for each target atom. The incident energy and atomic number as well as the static dipole polarizability have been used as input variables to find the functions that describe the total collisional cross sections of the scattering of electrons by alkali atoms. The experimental, calculated and predicted total collisional cross sections are compared. The discovered functions show a good match to the experimental data.

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