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Is it possible to obtain polarized positrons during multiple Compton backscattering process?

A. P. Potylitsyn
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Abstract

If a beam of unpolarized positrons (which is considered as a sum of two fractions with opposite helicities) passes through an intense circular polarized laser radiation these fractions may be separated. For high laser flash intensity each positron will interact with $k_0\gg$1 laser photons subsequently (linear multiple compton scattering process). Due to difference in the compton cross-section for positrons polarized in opposite directions the mean final energy of each fraction will be different. It allows to get a polarized positron beam using the momentum selection (with some intensity loss). Estimations show the possibility to obtain a positron beam with 35% longitudinal polarization and 25% intensity from the initial one for focussed laser flash with total energy 5J and positron beam with energy 5 GeV.

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A. P. Potylitsyn. 2003-04-03. Is it possible to obtain polarized positrons during multiple Compton backscattering process?. https://doi.org/10.1142/9789812702333_0015

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