Scaling test for Wilson twisted mass QCD

TL;DR

This paper presents a scaling test of Wilson twisted mass QCD demonstrating reduced lattice spacing errors and confirming O(a) improvement without additional terms, based on computations of meson mass and decay constants.

Contribution

First scaling test of Wilson twisted mass QCD showing automatic O(a) improvement and reduced lattice artifacts in quenched approximation.

Findings

Reduced lattice spacing errors observed

Consistent with O(a) improvement predictions

No additional improvement terms needed

Abstract

We present a first scaling test of twisted mass QCD with pure Wilson quarks for a twisting angle of pi/2. We have computed the vector meson mass and the pseudoscalar decay constant for different values of beta at fixed value of r_0 m_PS. The results obtained in the quenched approximation are compared with data for pure Wilson and non-perturbatively O(a) improved Wilson computations. We show that our results from Wilson twisted mass QCD show clearly reduced lattice spacing errors, consistent with O(a) improvement and without the need of any improvement terms added. These results thus provide numerical evidence of the prediction in ref. [1].