Related papers: $0^{++}$ scalar glueball in finite-width Gaussian …
Some recent developments in the phenomenology of the lightest scalar glueball are summarised. Tools for determining the gluonic content of a resonance of known mass, width and $J^{PC}$ from its branching fraction in radiative quarkonium…
We use SU(3) anisotropic lattice QCD at quenched level to study the 0++ glueball correlator at various temperature taking into account the possible existence of the thermal width in the ground-state peak. For this purpose, we adopt the…
We perform a calculation of the glueball spectrum for $N_f=4$ degenerate dynamical fermions with masses corresponding to light pions. We do so by making use of ensembles produced within the framework of maximally twisted fermions by the…
We resume the investigation of the ground-state pseudoscalar glueball, $J^{PC}=0^{-+}$, by computing its two- and three-body decays into vector and axial-vector quark-antiquark meson fields additional to scalar and pseudoscalar mesons…
QCD theory predicts the existence of glueballs, but so far all experimental endeavors have failed to identify any such states. To remedy this discrepancy between QCD, which has proven to be a successful theory for strong interactions, and…
For a complete description of the physical properties of low-energy QCD, it might be advantageous to first reformulate QCD in terms of gauge-invariant dynamical variables, before applying any approximation schemes. Using a canonical…
The spectrum of glueballs with quantum numbers $J^\mathsf{PC}=0^{\pm+},2^{\pm+},3^{\pm+},4^{\pm+}$ is calculated in quenched quantum chromodynamics from bound state equations. The input is taken from a parameter-free calculation of two- and…
Building on earlier results on holographic bulk dynamics in confining gauge theories, we compute the spin-0 and spin-2 spectra of gauge theories dual to the non-singular Maldacena-Nunez and Klebanov-Strassler supergravity backgrounds. We…
The sum rules for the spin dependent structure function $g_1^{ab}$ in the null-plane formalism corresponding to the moment at $n=0$ has been transformed to the sum rule which relates the $g_1^{ab}$ with the cross section of the isovector…
Within the framework of the generalized linear sigma model, a comprehensive analysis of scalar and pseudoscalar glueballs and their mixing with mesons is presented. The Lagrangian of the model contains two chiral nonets, a quark-antiquark…
Nonperturbative Wilson coefficients of the operator product expansion (OPE) for the spin-0 glueball correlators are derived and analyzed. A systematic treatment of the direct instanton contributions is given, based on realistic instanton…
The isosinglet scalar mesons $f_0(1710)$, $f_0(1500)$, $f_0(1370)$ and their mixing are studied. Two recent lattice results are employed as the starting point; one is the approximate SU(3) symmetry in the scalar sector above 1 GeV for the…
We investigate the glueball spectrum of a strongly coupled gauge theory with two dynamical scales. The main tool is the use of the gauge/gravity duality. The model we study has a known graviational dual, which arises from a type IIB D-brane…
The existence of glueballs, bound states of gluons, is one of the basic predictions of QCD; the lightest state is expected to be a scalar. The experimental situation, however, is still ambiguous. The existence of f_0(1370) would point to a…
We present a constituent two-gluon description of the lowest-lying glueball states in pure Yang--Mills theory, calibrated against quenched lattice results. The framework incorporates an instanton-induced dynamical gluon mass, Casimir-scaled…
We scrutinize the determination of glueball masses in pure Yang-Mills theory from functional equations, i.e. Dyson-Schwinger and Bethe-Salpeter equations. We survey the state-of-the-art input (dressed propagators and vertices) with an…
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…
We review standard holographic derivations of the scalar glueball spectra and emphasize computational assumptions which rely strongly on the original AdS/CFT correspondence, and those which are more arbitrary. In the soft-wall model, we…
The gluonic widths of four leading glueball candidates are determined from their production in radiative quarkonium decays, allowing quantitative estimation of their glue content. Lattice predictions for the scalar and tensor channels seem…
We employ two simple and robust results to constrain the mixing matrix of the isosinglet scalar mesons $f_0(1710)$, $f_0(1500)$, $f_0(1370)$: one is the approximate SU(3) symmetry empirically observed in the scalar sector above 1 GeV and…