In search of a scaling scalar glueball

Anisotropic lattices are an efficient means of studying the glueballs of QCD, however problems arise with simulations of the lightest, scalar state. The mass is strongly dependent on the lattice spacing, even when a mean-field improved gluon action is used. The nature and cause of these errors are discussed and the scaling properties of the scalar from different lattice actions are presented.Comment: LATTICE98(improvement

Improved gluonic actions on anisotropic lattices

The use of novel perturbatively-improved gluonic actions on anisotropic lattices in which the temporal spacing is much smaller than that in the spatial directions is discussed. Such actions permit more efficient measurements of noisy correlation functions, such as glueball correlators, on coarse lattices. A derivation of these actions at tree-level is outlined; mean-field link renormalization plays a crucial role in their construction. Results for the low-lying glueball masses and the heavy-quark potential are presented.Comment: 3 pages, 2 figures, uses espcrc2.sty and epsf.sty. Talk presented at LATTICE96(improvement

Baryon spectroscopy on the lattice: recent results

Progress in determining the baryon spectrum using computer simulations of quarks and gluons in lattice QCD are summarized and some future plans are outlined.Comment: 5 pages, 4 figures, talk presented at the Conference on the Intersections of Particle and Nuclear Physics, New York, NY, May 19-24, 2003, submitted to American Institute of Physics Conference Proceedings. After publication, it will be found at http://proceedings.aip.org/proceedings

Glueball Masses in Relativistic Potential Model

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 between two gluons are the short-range. We were to calculate the glueball masses with used screened potential.Comment: 7 pages, LaTe

The Improvement Program in Nonrelativistic Lattice QCD

Progress in the improvement program in nonrelativistic lattice QCD is outlined. The leading radiative corrections to the heavy-quark mass renormalization, energy shift, and two important kinetic coupling coefficients are presented. The reliability of tadpole-improved perturbation theory in determining the energy shift and mass renormalization is demonstrated.Comment: 3 pages in uuencoded-compressed-PostScript format, to appear in the Proceedings of LATTICE 93, Dallas, USA, October 1993; Edinburgh Preprint 93/53

Perturbative Matching of Heavy-Light Currents with NRQCD Heavy Quarks

We present further results for one-loop matching of heavy-light axial and vector currents between continuum QCD and a lattice theory with NRQCD heavy quarks and massless clover quarks.Comment: LATTICE98(heavyqk