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arXiv · nucl-th/0603025

Relativistic interactions for the meson-two-nucleon system in the clothed-particle unitary representation

Abstract

The method of unitary clothing transformations put forward in relativistic quantum field theory (QFT) by Greenberg and Schweber and developed by Shirokov is applied to construct a new family of interactions in the meson-two-nucleon system. Along with a brief exposition of its basic elements we show a specific transition from the initial ``bare'' one-meson and one-nucleon operators and states to their physical ``clothed'' counterparts. We emphasize that the clothing transformations in question do not alter the original total Hamiltonian, but provides a conceptually more transparent representation of the same Hamiltonian in terms of a new set of operators for particles with physical properties and their relativistic interactions. The Hermitian and energy-independent interaction operators for the processes piN -> piN, NN -> NN and NN -> pi NN are derived starting from the Yukawa-type couplings between fermions (nucleons and antinucleons) and bosons (pi-, eta-, rho-, omega-mesons, etc.). These types of interaction have a distinctive off-energy-shell structure which is naturally generated by the unitary transformation that removes from the Hamiltonian the (three-leg) piNN vertex coupling.

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V. Yu. Korda, L. Canton, A. V. Shebeko. 2006-03-08. Relativistic interactions for the meson-two-nucleon system in the clothed-particle unitary representation. https://doi.org/10.1016/j.aop.2006.07.010

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