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arXiv · 1410.8751

Isoscalar mesons upon unbreaking of chiral symmetry

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

In a dynamical lattice simulation with the overlap Dirac operator and $N_f=2$ mass degenerate quarks we study all possible $J=0$ and $J=1$ correlators upon exclusion of the low lying "quasi-zero" modes from the valence quark propagators. After subtraction of a small amount of such Dirac eigenmodes all disconnected contributions vanish and all possible point-to-point $J=0$ correlators with different quantum numbers become identical, signaling a restoration of the $SU(2)_L \times SU(2)_R \times U(1)_A$. The original ground state of the $π$ meson does not survive this truncation, however. In contrast, in the $I=0$ and $I=1$ channels for the $J=1$ correlators the ground states have a very clean exponential decay. All possible chiral multiplets for the $J=1$ mesons become degenerate, indicating a restoration of an $SU(4)$ symmetry of the dynamical QCD-like string.

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M. Denissenya, L. Ya. Glozman, C. B. Lang. 2015-01-20. Isoscalar mesons upon unbreaking of chiral symmetry. https://doi.org/10.1103/physrevd.91.034505

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