Non-perturbative scaling tests of twisted mass QCD

TL;DR

This paper investigates the scaling behavior of twisted mass lattice QCD with improved Wilson fermions, demonstrating effective O(a) improvement and small cutoff effects in meson observables within a moderate computational setup.

Contribution

It provides a non-perturbative scaling test of twisted mass QCD with O(a) improvement using Schrödinger functional boundary conditions in the quenched approximation.

Findings

O(a) improvement effectively reduces cutoff effects

Residual cutoff effects are small in meson observables

Scaling behavior is confirmed in a moderate-sized lattice

Abstract

We present a scaling study of lattice QCD with O(a) improved Wilson fermions and a chirally twisted mass term. In order to get precise results with a moderate computational effort, we have considered a system of physical size of 0.75^3 * 1.5 fm^4 with Schroedinger functional boundary conditions in the quenched approximation. Looking at meson observables in the pseudoscalar and vector channels, we find that O(a) improvement is effective and residual cutoff effects are fairly small.