Related papers: The Spin-Spin Dynamics of Glueballs
The spin of a glueball is usually taken as coming from the spin (and possibly the orbital angular momentum) of its constituent gluons. In light of the difficulties in accounting for the spin of the proton from its constituent quarks, the…
We evaluate the infinite volume, continuum limit of glueball masses in the valence (quenched) approximation to lattice QCD. For the lightest scalar and tensor states we obtain masses of $1648 \pm 58$ MeV and $2267 \pm 104$ MeV,…
We briefly review the computational strategy we have recently introduced for computing glueball masses and matrix elements, which achieves an exponential reduction of statistical errors compared to standard techniques. The global symmetries…
We report the progress on the lattice QCD calculation of the glue spin contribution to proton spin. This calculation is carried out with valence overlap fermion on 2+1 flavor DWF gauge configurations at two lattice spacings with the…
The problem of glueball mass spectra using the relativistic Dirac equation is studied. Also the Breit-Fermi approach used to obtaining hyperfine splitting in glueballs. Our approach is based on the assumption, that the nature and the forces…
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…
We determine spins of more than 100 low lying glueball states in $D=2+1$ dimensional $SU(4)$ gluodynamics by a lattice calculation. We go up to $J=8$ in the spin value. We compare the resulting spectrum with predictions of the Axionic…
We present the first 2+1 flavour spectrum measurements of glueball states using high statistics simulations with improved staggered fermions. We find a spectrum consistent with quenched measurements of scalar, pseudoscalar andtensor…
A strong coupling calculation of glueball masses based on the duality between supergravity and Yang-Mills theory is presented. Earlier work is extended to non-zero spin. Fluctuations in the gravitational metric lead to the 2^{++} state on…
Conventional lattice gauge theory assigns the lowest spin compatible with the symmetry channel of a given operator to the state coupling to that operator. Operators on a cubic lattice, however, are only defined on angles of pi/2, hence…
A new meson mass relation for meson nonet is given after considering mixing with glueball. The mixing between pseudoscalar mesons and pseudoscalar glueball will decrease the mass of glueball by about 500 Mev. So, according to the predicted…
A numerical study of the string tension and of the masses of the lowest-lying glueballs is performed in SU($N$) gauge theories for $2 \le N \le 8$ in D=3+1 and $2 \le N \le 6$ in D=2+1. It is shown that for the string tension a smooth $N…
We study the interaction of scalar glueball with quark-antiquark and four-quark spinless meson fields within the framework of a generalized linear sigma model in which the trace anomaly of QCD is exactly realized. To determine the pure…
The quenched spectrum of glueballs with positive charge parity is calculated from two-body bound state equations. As input, a self-contained solution for the primitively divergent correlation functions from Dyson-Schwinger equations is…
It is shown that the eigenstates of the quantized simplest closed (elliptic) Nambu -- Goto string, called glueballs, have quantum numbers I^Gj^{PC}=0^+j^{++}. Lightest glueballs have spins j=0,1 and 2 and the same mass 1500 +/- 20 MeV. They…
We obtain the spectrum of glueball masses for the N=1 non-conformal cascade theory whose supergravity dual was recently constructed by Klebanov and Strassler. The glueball masses are calculated by solving the supergravity equations of…
We evaluate the infinite volume, continuum limit of glueball masses in the valence (quenched) approximation to lattice QCD. For the lightest states with $J^{PC}$ of $0^{++}$ and $2^{++}$, we obtain $m_0 = 1340 \pm 160$ MeV and $m_2 = 1900…
We present a lattice QCD calculation of the glue spin $S_G$ in the nucleon for the first time. It was recently shown that the first moment of the glue helicity distribution could be obtained through the cross-product of the the electric…
Glueballs, an old and firm prediction of various QCD approaches (lattice QCD, bag models, AdS/QCD, effective models, etc.), have not yet been experimentally confirmed. While for glueballs below $2.6$ GeV some candidates exist, the situation…
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…