Related papers: Glueballs, Hybrids, Multiquarks. Experimental fact…
Quantum Chromodynamics (QCD), the generally accepted theory for the strong interactions, describes the interactions between quarks and gluons. The strongly interacting particles that are seen in nature are hadrons, which are composites of…
The non-Abelian nature of QCD suggests that particles that have a gluon constituent, such as glueballs or hybrids, should exist. Experiments WA76, WA91 and WA102 have performed a dedicated search for these states in central production using…
Hadrons, composed of quarks and gluons bound by Quantum Chromodynamics (QCD), traditionally classified as baryons (three quarks) and mesons (quark-antiquark pairs). Nothing in the theory of QCD stands against the existence of exotic hadrons…
I review a proposed pattern of the light scalar mesons with q\bar{q} mesons and glueball above 1 GeV and tetraquark mesoniums below 1 GeV. Several challenges and caveats of calculating these light scalar mesons with dynamical fermions are…
In this analysis, the so-called holographic graviton soft-wall model (GSW), first developed to investigate the glueball spectrum, has been adopted to predict the masses of hybrids with different quantum numbers. Results have been compared…
We review the status of an ongoing long-term lattice investigation of the spectrum and structure of tetraquark candidates. We focus on the light scalar meson $a_0(980)$. First steps regarding the study of a possibly existing $c c \bar{c}…
Identification of glueballs -- bound states of gauge bosons in Quantum Chromodynamics (QCD) -- is a very important open question in dynamics of the strong interaction. The search for the glueball ground state, carrying scalar quantum…
The lattice gauge theory technique for non-perturbative calculations in QCD is reviewed. The extraction of the continuum limit of lattice results is discussed with particular examples appropriate to hadron spectroscopy (the light hadrons…
The properties of scalar mesons and glueballs at finite temperature are analyzed through a {\it bottom-up} holographic approach. We focus on the spectral functions and mass spectra. A discussion on hadron dissociation and deconfinement…
The potential between two heavy-light mesons as a function of the heavy quark separation is calculated in quenched SU(3) lattice QCD. We study the case of heavy-light mesons with a static heavy quark and light quarks of mass close to the…
We study the spectra of light mesons as well as the dissociation of a quarkonium and monopole-anti monopole bound state in a gluon condensate background. In order to describe the confining phase we introduce an IR cutoff in two ways, namely…
The existence of glueballs within QCD is uncontroversial but their experimental verification is still in doubt. We discuss the new possibilities for a search of glueballs as the leading object in gluon jets at the LHC. We summarize previous…
This HADRON05 summary covers the topics of (1) mesons containing heavy quarks, and (2) theory. The new material discussed here is taken mainly from plenary presentations. We specifically emphasize new or recent results in spectroscopy that…
We discuss the ``spectroscopy'' of gluonic states in systems with two space dimensions, using simple models to mimic the results of lattice gauge theory computations. We first discuss the quantum numbers of these systems, including charge…
We investigate the mass spectra of scalar and vector glueballs in the so-called bottom-up approach of the AdS/QCD correspondence. The holographic model of QCD includes a static dilaton background field. We study the constraints on the…
We study $1+1$-dimensional $SU(N)$ gauge theories with adjoint scalar matter representations, based on a dimensional truncation of $2+1$ and $3+1$-dimensional pure QCD, which approximate the dynamics of transversely polarized gluons. The…
An unambiguous identification of glueballs in experiments will be of great significance, because their existence is an important test of QCD. The proposal, advanced here, is to experimentally search for glueballs as peaks in the invariant…
We investigate the light quarkonium hybrid mesons of various spin-parities in QCD. Considering different interpolating currents made of the valence light quarks and single gluon, we calculate the mass and current coupling of the strange and…
I briefly review lattice QCD, the valence (quenched) approximation, and the application of both to the determination of the mass and two-body decay couplings of the lightest scalar glueball. Results in agreement with the observed properties…
The status of lattice determinations of quarkonia and hybrid meson spectra is presented and compared with experiment. Both quenched and unquenched results are discussed. Hybrid meson decays are considered.