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arXiv · 1106.5619

On kinematical constraints in fermion-antifermion systems

S. Stoica·M. F. M. Lutz·O. Scholten
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Abstract

We consider the scattering of fermions off antifermions with spin 1/2 and 3/2. Starting from helicity partial-wave scattering amplitudes we derive transformations that eliminate all kinematical constraints. Such amplitudes are expected to satisfy partial-wave dispersion relations and therefore provide a suitable basis for data analysis and the construction of effective field theories. Our derivation relies on a decomposition of the various scattering amplitudes into suitable sets of invariant functions.

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S. Stoica, M. F. M. Lutz, O. Scholten. 2011-06-28. On kinematical constraints in fermion-antifermion systems. https://doi.org/10.1103/physrevd.84.125001

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