Positronium formation in electron capture from Methane molecule: Calculating partial differential and total cross section calculation of the first-order electron and nuclear amplitudes

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Abstract

In the present paper, the first-order electron and nuclear amplitudes are calculated in the framework of three-body formalism within corrected boundary conditions in the first order Born approximation and active electron model. Both the differential and total scattering cross sections, for the formation of positronium in collision of positron with methane molecule, are obtained using the differential amplitudes in the non-relativistic intermediate and high impact energies and are compared with the available experimental data. The selected impact energy and positron scattering angle fall in the ranges between 400 eV and 2 keV and 0 and to 180 degree, respectively. The cross section is computed in the center of mass frame and converted to the laboratory frame.

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