218 research outputs found
Topical Results on Lattice Chiral Fermions in the CFA
We report new results on the lattice regularization of the chiral Schwinger
model and the chiral U(1) model in four dimensions in the CFA.Comment: LATTICE98(chiral
Lattice QCD gluon propagators near transition temperature
Landau gauge gluon propagators are studied numerically in the SU(3)
gluodynamics as well as in the full QCD with the number of flavors
using efficient gauge fixing technique. We compare these propagators at
temperatures very close to the transition point in two phases : confinement and
deconfinement. The electric mass has been determined from the momentum
space longitudinal gluon propagator. Gribov copy effects are found to be rather
strong in the gluodynamics, while in the full QCD case they are weak ("Gribov
noise"). Also we analyse finite volume dependence of the transverse and
longitudinal propagators.Comment: 9 pages, 7 figure
Flux Tubes of Two- and Three-Quark System in Full QCD
We study the abelian color flux of two- and three-quark systems in the
maximally abelian gauge in lattice QCD with dynamical fermions. We find that
the abelian flux tube formed between quark and antiquark is very much the same
as in quenched QCD up to quark separations of 2fm. The profile of the
color electric field in three-quark system suggests ansatz, which might be
interpreted as the result of the vacuum pressure in the confined phase. In
order to clarify the flux structure, we investigate the color electric field of
the three-quark system splittting the abelian gauge field into the monopole and
photon parts.Comment: 4 pages, 4 figures, Talk given at XVI International Conference on
Particles and Nuclei (PaNic02),Osaka, Japan, Sep.30 - Oct.4, 200
On the interrelation between monopoles, vortices, topological charge and chiral symmetry breaking: an analysis using overlap fermions for SU(2)
We study the properties of configurations from which P-vortices on one hand
or Abelian monopoles on the other hand have been removed. We find that the zero
modes and the band of non-zero modes close to zero disappear from the spectrum
of the overlap Dirac operator, confirming the absence of topological charge and
quark condensate. The different behavior of the modified ensembles under
smearing compared to the unmodified Monte Carlo ensemble corroborates these
findings. The gluonic topological susceptibility rapidly approaches zero in
accordance with Q_{index}=0. The remaining (ultraviolet) monopoles without
vortices and -- to a less extent -- the remaining vortices without monopoles
are unstable under smearing whereas smearing of the unmodified Monte Carlo
ensemble effects the monopoles and vortices only by smoothing, reducing the
density only slightly.Comment: 13 pages, 5 figures, strongly revised, results added, one figure
added, accepted for publication, title changed
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