Excitations of torelon

The excitations of gluonic flux tube in a periodic lattice are examined. Monte Carlo simulations from an anisotropic lattice are presented and the comparison with effective string models is discussed.Comment: Talk at Lattice 2003; 3 pages, 4 figure

Non perturbative study of QCD on a 2+2 anisotropic lattice

We present preliminary results for a non perturbative determination of the parameters in the action required to restore Lorentz invariance in long distance correlators, using the static interquark potential. Comparison with analytical results is made and further applications are discussed.Comment: 3 pages, Lattice2003 (improvement

The First Calculation for the Mass of the Ground 4++4^{++} Glueball State on Lattice

Under the quenched approximation, we perform a lattice calculation for the mass of the ground $4^{++}$ glueball state in $E^{++}$ channel on a $D=3+1$ lattice. Our calculation shows that the mass of this state is $M_G(4^{++})=3.65(6)(18)GeV$, which rules out the $4^{++}$ or mainly $4^{++}$ glueball interpretation for $\xi(2230)$.Comment: 10 pages and 1 figur

Glueball Matrix Elements on Anisotropic Lattices

The glueball-to-vacuum matrix elements of local gluonic operators in scalar, tensor, and pseudoscalar channels are investigated numerically on several anisotropic lattices with the spatial lattice spacing in the range 0.1fm -- 0.2fm. These matrix elements are needed to predict the glueball branching ratios in $J/\psi$ radiative decays which will help to identify the glueball states in experiments. Two types of improved local gluonic operators are constructed for a self-consistent check, and the finite volume effects are also studied. The lattice spacing dependence of our results is very small and the continuum limits are reliably extrapolated.Comment: 3 pages, 3 figures, Lattice2003 (spectrum

Matching of the Heavy-Light Currents with NRQCD Heavy and Improved Naive Light Quarks

One-loop matching of heavy-light currents is carried out for a highly improved lattice action, including the effects of mixings with dimension 4 O(1/M) and O(a) operators. We use the NRQCD action for heavy quarks, the Asqtad improved naive action for light quarks, and the Symanzik improved glue action. These results are being used in recent heavy meson decay constant and semileptonic form factor calculations on the MILC dynamical configurations.Comment: 3 pages, 3 figures. Talk presented at Lattice2004(heavy

Static-light matrix elements on a dynamical anisotropic lattice

The static-light matrix element needed to determine $f_B$ is studied on an anisotropic lattice with $N_f=2$. The improvement in precision due to stout links and all-to-all propagators is investigated.Comment: Lattice2004(heavy), Fermilab, June 21-26, 2004. 3 page

Comment on the "Coupling Constant and Quark Loop Expansion for Corrections to the Valence Appeoximation" by Lee and Weingarten

Lee and Weingarten have recently criticized our calculation of quarkonium and glueball scalars as being "incomplete" and "incorrect". Here we explain the relation of our calculations to full QCD.Comment: 5 pages,2 epsfigs. Submitted to the Comment section of Phys. Rev. D 28th April 199

Quarks, Gluons and Frustrated Antiferromagnets

The Contractor Renormalization Group method (CORE) is used to establish the equivalence of various Hamiltonian free fermion theories and a class of generalized frustrated antiferromagnets. In particular, after a detailed discussion of a simple example, it is argued that a generalized frustrated SU(3) antiferromagnet whose single-site states have the quantum numbers of mesons and baryons is equivalent to a theory of free massless quarks. Furthermore, it is argued that for slight modification of the couplings which define the frustrated antiferromagnet Hamiltonian, the theory becomes a theory of quarks interacting with color gauge-fields.Comment: 21 pages, Late