29 research outputs found
Light Spectrum and Decay Constants in Full QCD with Wilson Fermions
We present results from an analysis of the light spectrum and the decay
constants f_{\pi} and f_V^{-1} in Full QCD with n_f=2 Wilson fermions at a
coupling of beta=5.6 on a 16^3x32 lattice.Comment: 3 pages, LaTeX with 4 eps figures, Talk presented at
LATTICE96(spectrum
Survey-Sami and Indigenous Research
Centre for Sami Studies at The University of Tromsø has by The Research Council of Norway been assigned to make a survey of Sami and Indigenous research going on in the Nordic countries
Transverse Structure of Nucleon Parton Distributions from Lattice QCD
This work presents the first calculation in lattice QCD of three moments of
spin-averaged and spin-polarized generalized parton distributions in the
proton. It is shown that the slope of the associated generalized form factors
decreases significantly as the moment increases, indicating that the transverse
size of the light-cone quark distribution decreases as the momentum fraction of
the struck parton increases.Comment: 4 pages, 1 figur
Calculation of Nucleon Electromagnetic Form Factors
The fomalism is developed to express nucleon matrix elements of the
electromagnetic current in terms of form factors consistent with the
translational, rotational, and parity symmetries of a cubic lattice. We
calculate the number of these form factors and show how appropriate linear
combinations approach the continuum limit.Comment: Lattice 2002 (hadronic matrix elements) 3 page
An Estimate of alpha_S from Bottomonium in Unquenched QCD
We estimate the strong coupling constant from the perturbative expansion of
the plaquette. The scale is set by the 2S-1S and 1P-1S splittings in
bottomonium which are computed in NRQCD on dynamical gauge configurations with
nf=2 degenerate Wilson quarks at intermediate masses. We have increased the
statistics of our spectrum calculation in order to reliably extrapolate in the
sea-quark mass. We find a value of alpha_MS(m_Z) = 0.1118(26) which is somewhat
lower than previous estimates within NRQCD.Comment: LATTICE98(heavyqk
Light Quark Physics with Dynamical Wilson Fermions
We present results for spectroscopy, quark masses and decay constants
obtained from SESAM's and TkL's large statistics simulations of QCD with two
dynamical Wilson fermions.Comment: 3 pages; to appear in the proceedings of Lat.'9
Masses of singlet and non-singlet 0++ particles
We compute the mass of the singlet 0++ state using both (psi_bar psi) and
Wilson loop operators from a N_f=2 lattice QCD calculation.Comment: Lattice2002(spectrum
Unquenching the Quark Model and Screened Potentials
The low-lying spectrum of the quark model is shown to be robust under the
effects of `unquenching'. In contrast, the use of screened potentials is shown
to be of limited use in models of hadrons. Applications to unquenching the
lattice Wilson loop potential and to glueball mixing in the adiabatic hybrid
spectrum are also presented.Comment: 6 pages, 3 ps figures, revtex. Version to appear in J. Phys.
Glueballs and string breaking from full QCD
We present results on the static potential, and torelon and glueball masses
from simulations of QCD with two flavours of dynamical Wilson fermions on
and lattices at .Comment: Talk presented by Gunnar Bali at International Symposium on Lattice
Field Theories (Lattice 97), Edinburgh, July 1997, 3 pages LaTeX
(epscrc2.sty) with 4 eps figure
Preliminary Calculation of from Green Functions with Dynamical Quarks
We present preliminary results on the computation of the QCD running coupling
constant in the scheme and Landau gauge with two flavours of
dynamical Wilson quarks. Gluon momenta range up to about 7 GeV ( 5.6,
5.8 and 6.0) with a constant dynamical-quark mass. This range already allows to
exhibit some evidence for a sizable correction to the asymptotic
behaviour, as in the quenched approximation, although a fit without power
corrections is still possible with a reasonable . Following the
conclusions of our quenched study, we take into account correction to
the asymptotic behaviour. We find , which leads to
. The latter result has to be taken as a
preliminary indication rather than a real prediction in view of the systematic
errors still to be controlled. Still, being two sigmas below the experimental
result makes it very encouraging.Comment: 14 pages, 3 figs., 2 tabs., revte
