Light hadrons from lattice QCD with light (u,d), strange and charm dynamical quarks

TL;DR

This paper reports on lattice QCD simulations with 2+1+1 dynamical quarks, measuring light pseudoscalar properties and low energy constants, while analyzing systematic effects and discretisation impacts.

Contribution

It provides high-precision results for light pseudoscalar masses and decay constants using Wilson twisted mass fermions with multiple lattice spacings and volumes, including systematic effect analysis.

Findings

Precise measurements of m_PS and f_PS in specified mass range

Determination of low energy constants f_0, l_3, l_4

Comparison of discretisation effects with N_f=2 results

Abstract

We present results of lattice QCD simulations with mass-degenerate up and down and mass-split strange and charm (N_f = 2+1+1) dynamical quarks using Wilson twisted mass fermions at maximal twist. The tuning of the strange and charm quark masses is performed at two values of the lattice spacing a~0.078 fm and a~0.086 fm with lattice sizes ranging from L~1.9 fm to L~2.8 fm. We measure with high statistical precision the light pseudoscalar mass m_PS and decay constant f_PS in a range 270 < m_PS < 510 MeV and determine the low energy parameters f_0, l_3 and l_4 of SU(2) chiral perturbation theory. We use the two values of the lattice spacing, several lattice sizes as well as different values of the light, strange and charm quark masses to explore the systematic effects. A first study of discretisation effects in light-quark observables and a comparison to N_f=2 results are performed.