The η′ meson at the physical point with Nf = 2 Wilson twisted mass fermions
We present results for the η′ meson and the topological susceptibility in Nf = 2 flavour lattice QCD. The results are obtained using Wilson twisted mass fermions at maximal twist with pion masses ranging from 340 MeV down to the physical point. A comparison to literature values is performed giving a handle on discretisation effects.
Topological susceptibility and η′ meson mass from Nf=2 lattice QCD at the physical point
In this paper we explore the computation of topological susceptibility and ${\ensuremath{\eta}}^{\ensuremath{'}}$ meson mass in ${N}_{f}=2$ flavor QCD using lattice techniques with a physical value of the pion mass as well as larger pion mass values. We observe that the physical point can be reached without a significant increase in the statistical noise. The mass of the ${\ensuremath{\eta}}^{\ensuremath{'}}$ meson can be obtained from both fermionic two point functions and topological charge density correlation functions, giving compatible results. With the pion mass dependence of the ${\ensuremath{\eta}}^{\ensuremath{'}}$ mass being flat we arrive at ${M}_{{\ensuremath{\eta}}^{\ensuremath…