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arXiv · 1402.1887

Symmetries of mesons after unbreaking of chiral symmetry and their string interpretation

M. Denissenya·L. Ya. Glozman·C. B. Lang
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Abstract

Using the chirally invariant overlap Dirac operator we remove its lowest-lying quasizero modes from the valence quark propagators and study evolution of isovector mesons with J=1. At the truncation level about 50 MeV SU(2)_L \times SU(2)_R and U(1)_A symmetries get restored. However, we observe a degeneracy not only within the chiral and U(1)_A multiplets, but also a degeneracy of all possible chiral multiplets, i.e., the observed quantum levels have a symmetry larger than U(2)_L \times U(2)_R and their energy does not depend on the spin orientation of quarks and their parities. We offer a possible interpretation of these energy levels as the quantum levels of the dynamical QCD string. The structure of the radial J=1 spectrum is compatible with E =(n_r +1)\hbarωwith \hbarω= 900 \pm 70 MeV.

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M. Denissenya, L. Ya. Glozman, C. B. Lang. 2014-04-26. Symmetries of mesons after unbreaking of chiral symmetry and their string interpretation. https://doi.org/10.1103/physrevd.89.077502

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