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A Covariant Method for Calculating Amplitudes of Processes Involving Polarized Spin 1/2 Particles. Calculation of the Interference Terms in their Cross Sections

Alexander L. Bondarev
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Abstract

A covariant method is proposed for calculating the amplitudes of processes involving polarized spin 1/2 particles. It is suitable for calculating the interference terms in the cross sections of such processes. As an illustration, expressions are given for the amplitudes of electron-electron scattering in the lowest order of perturbation theory and expressions for the electron current in the case of emission of two bremsstrahlung photons in the ultrarelativistic limit.

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Alexander L. Bondarev. 1997-01-20. A Covariant Method for Calculating Amplitudes of Processes Involving Polarized Spin 1/2 Particles. Calculation of the Interference Terms in their Cross Sections. https://arxiv.org/abs/hep-ph/9701333

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