$η$-glueball mixing from $N_f=2$ lattice QCD

Abstract

We perform the first lattice study on the mixing of the isoscalar pseudoscalar meson η and the pseudoscalar glueball G in the N f = 2 QCD at the pion mass mπ ≈ 350 MeV. The η mass is determined to be mη = 714.1(5.4) MeV. Through the Witten-Veneziano relation, this value can be matched to a mass value of ∼ 935 MeV for the SU (3) counterpart of η. Based on a large gauge ensemble, the η − G mixing energy and the mixing angle are determined to be |x| = 107(14) MeV and |θ| = 3.47(46) • from the η − G correlators that are calculated using the distillation method. It is also found that mη can be correctly derived from η − ηc correlators with ηc being the pseudoscalar charmonium. We conclude that the η − G mixing is tiny and the topology induced interaction contributes most of η mass owing to the QCD UA(1) anomaly.

$T_{cc}^{+}(3875)$ relevant $DD^*$ scattering from $N_f=2$ lattice QCD

“…We use the tadpole improved anisotropic clover fermion action for light u, d quarks [50,51] and tadpole improved gauge action [52,53]. The renormalized aspect ratio is determined to be ξ = a s /a t = 5.3, and the temporal lattice spacing is set to be a −1 t = 6.894 (51) GeV [54]. Using the a t and the ξ, we get a s ≈ 0.152(1) fm.…”