Hybrid meson decay from the lattice

Abstract

We discuss the allowed decays of a hybrid meson in the heavy quark limit. We deduce that an important decay will be into a heavy quark non-hybrid state and a light quark meson, in other words, the de-excitation of an excited gluonic string by emission of a light quark-antiquark pair. We discuss the study of hadronic decays from the lattice in the heavy quark limit and apply this approach to explore the transitions from a spin-exotic hybrid to $\chi_b \eta$ and $\chi_b S$ where $S$ is a scalar meson. We obtain a signal for the transition emitting a scalar meson and we discuss the phenomenological implications

Axial resonances a 1(1260), b 1(1235) and their decays from the lattice

“…The width Γ[b 1 → ωπ] was extracted based on the amplitude method [17] and reasonable agreement with experiment was found (see figure 3 of [16]). The a 1 has never been simulated taking into account its strong decay, with exception of our preliminary results [18].…”

Hybrid mesons

“…The first lattice computation of a hadronic transition was made by the UKQCD collaboration for the case of heavy hybrids [43]. The static quark limit imposes important constraints on the decay process since the quark-antiquark configuration must remain unchanged.…”

Exotic meson decay widths using lattice QCD

“…Hybrid meson decay widths have been studied on the lattice in the heavy quark limit [15] and, recently, for light quarks [14]. In those studies the time dependence (slope) of a normalized transition matrix element computed on the lattice is related to a decay width via Fermi's golden rule [35].…”

“…Attempts to calculate decay widths of hybrid mesons have been made using the bag model [11], the quark model extended by gluon flux tube degrees of freedom [12,13] and in lattice QCD [14,15].…”