Chiral Loop Effects in the Quenched Scalar Isovector Propagator

TL;DR

This paper investigates the scalar isovector meson propagator in quenched QCD, revealing that at light quark masses, it is dominated by quenched chiral loop effects involving the eta'-pi intermediate state, consistent with theoretical predictions.

Contribution

It provides the first detailed analysis of quenched chiral loop effects in the scalar isovector propagator, confirming theoretical models with lattice QCD data.

Findings

Quenched chiral loops dominate at light quark masses.

Time and pion mass dependence match quenched chiral perturbation theory.

The eta'-pi intermediate state is crucial in the propagator behavior.

Abstract

The scalar isovector meson propagator is studied in quenched QCD. For the lightest quark masses used, this propagator is dominated by a quenched chiral loop effect associated with the $\eta'$-$\pi$ two-meson intermediate state. Both the time dependence and the pion mass dependence of the effect are well-described by quenched chiral perturbation theory.