Related papers: Glueballs, Constituent Gluons and Instantons
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…
The correlator of the square of the Yang-Mills field-strength tensor corresponds to a scalar glueball, i.e., to a bound-state formed by gluonic ingredients only. It has quantum numbers 0++ and its mass, as predicted by different theoretical…
We study the contribution of instantons to the binding and the mass of the lightest scalar glueball, in gluondynamics. We show that the short-range correlations introduced by such non-perturbative vacuum fluctuations are sufficient to give…
According to lattice simulations and other theoretical approaches, the scalar glueball is the lightest state in the Yang-Mills sector of QCD. Since within this sector the scalar glueball is stable, the scattering between two glueballs is a…
Theoretical ideas related to the existence of glueballs in QCD are reviewed. These include non-perturbative phenomena such as confinement, instantons, vacuum condensates and renormalons. We also discuss glueball dominance of the trace of…
We include instanton effects in QCD sum rules for coupled scalar glueballs and mesons. We find a light glueball/sigma as in earlier studies without instantons, but in a lattice-type pure instanton model the light glueball/sigma is not…
We analyze 2+1 dimensional Yang-Mills theory regularized on a lattice with twisted boundary conditions in the spatial directions. In previous work it was shown that the observables in the non-zero electric flux sectors obey the so-called…
The strongly coupled phase of Yang-Mills plasma with arbitrary gauge group is studied in a $T$-matrix approach. The existence of lowest-lying glueballs, interpreted as bound states of two transverse gluons (quasi-particles in a many-body…
We calculate the mass of the lowest lying spin two glueball in N=1 super Yang-Mills from the dual Klebanov-Strassler background. We show that the Regge trajectory obtained is linear; the 0++, 1-- and 2++ states lie on a line of slope 0.23…
Using a simple relativistic QFT model of scalar fields we demonstrate that the analytic confinement (propagator is an entire function in the complex $p^2$--plane) and the weak coupling constant lead to the Regge behaviour of the…
Lattice computations with excited SU(3) representations suggest that the confining gluon-gluon interaction complies with the Casimir scaling. The constituent gluon models have also been assuming the Casimir scaling. Inspired in type-II…
In a model with dynamical gluon mass, we investigate the bound states of two and three gluons via a Schr\"odinger equation. The short distance potential is approximated by one-gluon-exchange while the long distance part is assumed to be of…
Using a simple relativistic QFT model of scalar fields we demonstrate that the analytic confinement (propagator is an entire function in the complex p^2-plane) and the weak coupling constant lead to the Regge behaviour of the two-particle…
We provide a new, independent, and analytic estimate of the lowest glueball mass, and we found it at 1661 MeV within a relativistic quantum-field model based on analytic confinement. The conventional mesons and the weak decay constants are…
We report the masses of the lightest spin-0 and spin-2 glueballs obtained in an extensive lattice study of the continuum and infinite volume limits of $Sp(N_c)$ gauge theories for $N_c=2,4,6,8$. We also extrapolate the combined results…
Glueballs are bound states in the spectrum of quantum chromodynamics which consist only of gluons. They belong to the group of exotic hadrons which are widely studied experimentally and theoretically. We summarize how to calculate glueballs…
We show that the lattice glueball masses $M_G$ versus $N$ in SU($N$) and Sp($2N$) Yang-Mills theories scale as $\frac{M_G}{\sqrt\sigma}\sim \sqrt{\frac{C_2(adj)}{C_2(f)}}$, with $\sigma$ the fundamental string tension and $C_2(adj)$ and…
We present details of the analytic computation of the spectrum of lowest spin glueballs in pure Yang-Mills theory in 2+1 dimensions. The new ingredient is provided by the conjectured new non-trivial expression for the (quasi)Gaussian part…
We prove a theorem in QCD stating that in the limit of strong coupling, $g\to\infty$, the observed spectrum of glueballs in QCD is the same of a pure Yang-Mills theory, being mixing effects due to the next-to-leading order. A full effective…
The scalar glueball $G$ is the lightest particle of the Yang-Mills sector of QCD, with a lattice predicted mass of about $m_{G}\simeq1.7$ GeV. It is natural to investigate glueball-glueball scattering and the possible emergence of a bound…