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Quark-Antiquark Bound States in an Extended QCD_2 Model

Pedro Labrana·Jorge Alfaro·Alexander A. Andrianov
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Abstract

We study an extended QCD model in 2D obtained from QCD in 4D by compactifying two spatial dimensions and projecting onto the zero-mode subspace. This system is found to induce a dynamical mass for transverse gluons -- adjoint scalars in QCD(2), and to undergo a chiral symmetry breaking with the full quark propagators yielding non-tachyonic, dynamical quark masses, even in the chiral limit. We construct the hadronic color singlet bound-state scattering amplitudes and study quark-antiquark bound states which can be classified in this model by their properties under Lorentz transformations inherited from 4D.

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Pedro Labrana, Jorge Alfaro, Alexander A. Andrianov. 2004-12-27. Quark-Antiquark Bound States in an Extended QCD_2 Model. https://arxiv.org/abs/hep-th/0412248

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