Related papers: Hybrid Mesons
Mesons with quantum numbers $J^{PC}=1^{-+}$ cannot be represented as simple quark-antiquark pairs. We explore hybrid configurations in the light meson sector comprising a quark, an antiquark and an excited gluon, studying the properties of…
We interpret the spectrum of meson states recently obtained in non-perturbative lattice QCD calculations in terms of constituent quark-antiquark bound states and states, called `hybrids', in which the qqbar pair is supplemented by an…
The status of non-perturbative QCD calculations for mesons with gluonic excitation is presented. Lattice results for the glueball spectrum are reviewed. For hybrid mesons, the heavy quark results are summarised and new results are presented…
The exploration of exotic mesons, which transcend the conventional quark-antiquark framework, is pivotal for advancing our understanding of QCD and the strong interaction. Among these, states possessing the quantum numbers $J^{PC}=1^{-+}$,…
Quantum Chromodynamics (QCD) is the theory that describes how hadrons are built from quarks and gluons via the strong interaction. Many predictions have been experimentally confirmed, but others remain under experimental investigation. Of…
Theoretical arguments are given in favour of existence of gluonic degrees of freedom at the constituent level. Models for hybrid mesons are discussed, and the predictions are compared with the data on meson spectroscopy in the light quark…
Within QCD, colourless states may be constructed corresponding to exotic matter outside of the traditional quark model. Experiments have recently observed tetraquark and pentaquark states, but no definitive hybrid meson signals have been…
Hybrid mesons consist of a quark-antiquark pair bound together by a gluonic field that is in an excited state. Measuring the spectrum of these states will provide valuable information on the gluonic degrees of freedom of QCD in the…
The vast majority of mesons can be understood as quark-antiquark states. Yet, various other possibilities exists: glueballs (bound-state of gluons), hybrids (quark-antiquark plus gluon), and four-quark states (either as diquark-antidiquark…
QCD theory allows the existence of states which cannot be built by the naive quark model; both theoretical arguments and experimental data confirm the hypothesis that gluons may have freedom degrees at the constituent level, and should be…
Hadron spectroscopy has received revitalised interest due to the discovery of states with unexpected properties. Discussed are the recent findings at BABAR, CLEO, BELLE and BES. A detailed report is given on the many experiments reporting…
Hybrid mesons, made from a quark, an antiquark and gluons, can have quantum numbers inaccessible to conventional quark-antiquark states. Confirmation of such states would give information on the role of "dynamical" color in low energy QCD.…
Hybrid (exotic) mesons, which are important predictions of quantum chromodynamics (QCD), are states of quarks and anti-quarks bound by excited gluons. First principle lattice study of such states would help us understand the role of…
The primary motivation of the GlueX experiment is to search for and ultimately study the pattern of gluonic excitations in the meson spectrum produced in $\gamma p$ collisions. Recent lattice QCD calculations predict a rich spectrum of…
Quantum Chromodynamics (QCD), the theory of strong interactions, in principle describes the interaction of quark and gluon fields. However, due to the self-coupling of the gluons, quarks and gluons are confined into hadrons and cannot exist…
This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{PC} = 2^{+-}$ that conventional…
We investigate light hybrid mesons composed of a light quark-antiquark pair and two gluons within the framework of QCD sum rules. We focus on states with quantum numbers $J^{\mathrm{PC}} = 0^{++}, 0^{+-}, 0^{-+}, 0^{--}$ and…
Since gluons in QCD are interacting fundamental constituents just as quarks are, we expect that in addition to mesons made from a quark and an antiquark, there should also be glueballs and hybrids (bound states of quarks, antiquarks and…
Hybrid mesons occupy a unique position in the hadronic spectrum, offering a valuable insight into the non-perturbative nature of the glue field. Hybrid states with exotic $J^{PC}$ quantum numbers, such as the $1^{-+}$, $0^{+-}$ and…
The models for hybrid mesons are discussed, in which the gluonic excitations manifest themselves as the vibrations of the quark- antiquark QCD string. The predictions for the spectra, decays and mixing with hadronic channels are presented.