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arXiv · hep-ph/9609525

From Current to Constituent Quarks: a Renormalization Group Improved Hamiltonian-based Description of Hadrons

Abstract

A model which combines the perturbative behavior of QCD with low energy phenomenology in a unified framework is developed. This is achieved by applying a similarity transformation to the QCD Hamiltonian which removes interactions between the ultraviolet cutoff and an arbitrary lower scale. Iteration then yields a renormalization group improved effective Hamiltonian at the hadronic energy scale. The procedure preserves the standard ultraviolet behavior of QCD. Furthermore, the Hamiltonian evolves smoothly to a phenomenological low energy behavior below the hadronic scale. This method has the benefit of allowing radiative corrections to be directly incorporated into nonperturbative many-body techniques. It is applied to Coulomb gauge QCD supplemented with a low energy linear confinement interaction. A nontrivial vacuum is included in the analysis via a Bogoliubov-Valatin transformation. Finally, the formalism is applied to the vacuum gap equation, the quark condensate, and the dynamical quark mass.

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BibTeXRIS

A. P. Szczepaniak, E. S. Swanson. 1996-09-30. From Current to Constituent Quarks: a Renormalization Group Improved Hamiltonian-based Description of Hadrons. https://doi.org/10.1103/physrevd.55.1578

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