Lattice study of "f$_{0}$(600) or $\sigma$"

TL;DR

This study uses full-QCD lattice simulations with Wilson fermions to investigate the sigma meson, providing preliminary evidence of a pole with a mass comparable to the rho meson.

Contribution

First lattice QCD study of the sigma meson using full-QCD simulations with Wilson fermions and disconnected diagram evaluations.

Findings

Indications of a sigma meson pole near rho mass.

Larger hopping parameters reduce noise in correlator data.

Preliminary results suggest the sigma meson exists in this framework.

Abstract

We investigate the propagator of "f$_{0}$(600) or the $\sigma$" by the full-QCD simulation with Wilson fermions. We calculate the mesonic correlator in the I=0, $J^P=0^{+}$ channel on the $8^{3} \times 16$ lattice. Plaquet action and Wilson fermion action are adopted. A coupling constant $\beta$ is set to 4.8 and three kinds of hopping parameter, $\kappa$=0.1846, 0.1874 and 0.1891 are assayed. The disconnected diagram in the propagator is evaluated through taking average over 500 or 1000 Z2 noise. Simulations with the larger hopping parameter provide us with less noisy results. Though the statistics is not yet enough, our results indicate the existence of a pole with a mass in almost the same order as that of the $\rho$.