Eight very excited spectra and one possible axion in SU(3) lattice gauge theory

Abstract

We compute the spectra of flux tubes formed between a static quark antiquark pair up to a significant number of excitations and for eight symmetries of the flux tubes, up to $\Delta_u$, using pure $SU(3)$ gauge lattice QCD in 3+1 dimensions. To accomplish this goal, we use a large set of appropriate operators, an anisotropic tadpole improved action, smearing techniques, and solve a generalized eigenvalue problem. Moreover, we compare our results with the Nambu-Goto string model to evaluate possible tensions which could be a signal for novel phenomena. Especially, we provide evidence for the coupling of a massive particle, say an axion, to the $\Sigma_g^-$, $\Sigma_u^-$, and $\Sigma_u^{-*}$ flux tube with approximate masses $ 2.25\sqrt{\sigma}$, $1.85\sqrt{\sigma}$, $3.30\sqrt{\sigma}$, respectively.