Numerical properties of staggered quarks with a taste-dependent mass term

TL;DR

This paper investigates the numerical properties of staggered Dirac operators with taste-dependent mass terms, comparing them to traditional operators, and explores their potential for efficient lattice QCD simulations without fine-tuning.

Contribution

It introduces and analyzes taste-dependent mass staggered operators, highlighting their advantages over traditional operators and their potential to simplify simulations in lattice QCD.

Findings

Hoelbling operator can simulate two degenerate flavors without additive mass renormalization.

Taste-dependent mass operators exhibit favorable topological and spectral properties.

Potential for use without overlap construction to reduce computational cost.

Abstract

The numerical properties of staggered Dirac operators with a taste-dependent mass term proposed by Adams [1,2] and by Hoelbling [3] are compared with those of ordinary staggered and Wilson Dirac operators. In the free limit and on (quenched) interacting configurations, we consider their topological properties, their spectrum, and the resulting pion mass. Although we also consider the spectral structure, topological properties, locality, and computational cost of an overlap operator with a staggered kernel, we call attention to the possibility of using the Adams and Hoelbling operators without the overlap construction. In particular, the Hoelbling operator could be used to simulate two degenerate flavors without additive mass renormalization, and thus without fine-tuning in the chiral limit.