Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · hep-lat/0009021

Non-perturbative results for the coefficients b_m and b_a-b_p in O(a) improved lattice QCD

Marco Guagnelli·Roberto Petronzio·Juri Rolf·Stefan Sint·Rainer Sommer·Ulli Wolff
View original source ↗Read source document ↗Export metadata ↓

Abstract

We determine the improvement coefficients b_m and b_a-bp in quenched lattice QCD for a range of beta-values, which is relevant for current large scale simulations. At fixed beta, the results are rather sensitive to the precise choices of parameters. We therefore impose improvement conditions at constant renormalized parameters, and the coefficients are then obtained as smooth functions of g_0^2. Other improvement conditions yield a different functional dependence, but the difference between the coefficients vanishes with a rate proportional to the lattice spacing. We verify this theoretical expectation in a few examples and are therefore confident that O(a) improvement is achieved for physical quantities. As a byproduct of our analysis we also obtain the finite renormalization constant which relates the subtracted bare quark mass to the bare PCAC mass.

Explore related subjects

hep-lat

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Marco Guagnelli, Roberto Petronzio, Juri Rolf, Stefan Sint, Rainer Sommer, Ulli Wolff. 2000-09-19. Non-perturbative results for the coefficients b_m and b_a-b_p in O(a) improved lattice QCD. https://doi.org/10.1016/s0550-3213(00)00675-1

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Subtraction method for disconnected diagrams in full QCD

Disconnected diagrams remain a major challenge for precision lattice QCD calculations because of their large statistical fluctuations. We investigate a subtraction method based on a domain decomposition of the Dirac operator, yielding a biased but substantially less noisy estimator. Applying the method to charmonium disconnected correlators computed using distillation, we achieve a variance reduction of about three orders of magnitude at only twice the computational cost, providing a practical alternative to completely neglecting disconnected contributions.

hep-lat↗
arXiv2026

Progress on $Sp(4)$ lattice theories with Grid: Möbius domain wall fermions and continuum extrapolations

We present preliminary results obtained in the first extensive study of the Möbius domain wall fermion (MDWF) lattice formulation of the four-dimensional Sp(4) gauge theory coupled to two dynamical fermions transforming in the fundamental representation. This theory is important for extensions of the Standard Model, as it provides the microscopic origin for both composite Higgs and dark matter models based on the SU(4)/Sp(4) coset. We scan the space of bare lattice parameters, including those entering the MDWF, and monitor spurious effects, such as the residual mass. We identify optimised regions of parameter space in which lattice artefacts affecting the global symmetries of the theory are suppressed. We then perform preliminary measurements of the lightest pseudoscalar and vector meson masses, together with the pseudoscalar decay constant. We demonstrate the potential of the MDWF formulation to enable continuum-limit extrapolations with reduced lattice discretisation effects.

hep-lat↗
arXiv2026

Boundary Condition dependent Universality Classes on a Hyperbolic Lattice

We study the ferromagnetic Ising model on finite hyperbolic tessellations of Euclidean AdS$_2$ with open and wired boundary conditions. Because a finite fraction of spins remains at the boundary as the lattice grows, these conditions select distinct thermodynamic behaviours. In the $\{5,4\}$ tessellation, Monte-Carlo simulations using efficient worm algorithms on open boundaries (OBC) yield a transition near $β_c J=0.632(3)$, with susceptibility data collapsing under scaling by the total number of spins $N$. The fitted finite-size exponents, $1/\barν \simeq 0.162$ and $γ/\barν \simeq 0.743$, differ substantially from the mean-field volume scaling. Wired boundaries (WBC), which correlate boundary spins, instead show a transition around $β_c J=0.348(4)$ to an ordered phase consistent with the mean-field exponents. While the mean-field criticality with WBC is consistent with previous studies and with the suppression of independent boundary fluctuations, the OBC exponents hint at the presence of a new universality class. Results from other tessellations support the robustness of the observed scaling with OBC. We discuss a possible route to interpolate between the different boundary conditions. Our findings show that boundary dynamics must be specified when characterizing critical behaviour on hyperbolic lattices.

hep-lat↗