Mon·Oct 22, 2001Monday·October 22, 2001

1. 01*

   N* Masses from an Anisotropic Lattice QCD Action

   F.X. Lee🇺🇸 · D.B. Leinweber🇦🇺 · L. Zhou🇺🇸 · J. Zanotti🇦🇺 · S. Choe🇯🇵

   We report N* masses in the spin 3/2 sector from a highly-improved anisotropic action. States with both positive and negative parity are isolated via a parity projection method. The extent to which spin projection is needed is examined. The gross features of the splittings from the nucleon ground state show a trend consistent with experimental results at the quark masses explored.

   hep-lathep-phnucl-thNucl.Phys.B Proc.Suppl.(2002)·17 citations
2. 02*

   The Maximal Abelian Gauge in SU(3) Lattice Gauge Theory

   William W. Tucker🇺🇸 · John D. Stack🇺🇸

   We gauge fix 600 SU(3) beta=6.0 configurations on a 16^4 lattice to a simple form of the maximal abelian gauge. We project the SU(3) valued links to the U(1)xU(1) subgroup, and extract U(1)xU(1) and monopole string tensions. After gauge fixing to the indirect center gauge, the U(1)xU(1) links are projected to Z(3) and a vortex string tension is measured. The vortex and magnetic current densities are measured.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·6 citations
3. 03*

   Quenched twisted mass QCD at small quark masses and in large volume

   M. Della Morte (Univ. of Milano Bicocca)🇮🇹 · R. Frezzotti (Univ. of Milano Bicocca)🇮🇹 · J. Heitger (Univ. of Muenster)🇩🇪

   As a test of quenched lattice twisted mass QCD, we compute the non-perturbatively O($a$) improved pseudoscalar and vector meson masses and the pseudoscalar decay constant down to $M_{\mathrm{PS}}/M_{\mathrm{V}}=0.467(13)$ at $\beta =6$ in large volume. We check the absence of exceptional configurations and -- by further data at $\beta =6.2$ -- the size of scaling violations. The CPU time cost for reaching a given accuracy is close to that with ordinary Wilson quarks at $M_{\mathrm{PS}}/M_{\mathrm{V}}\simeq 0.6$ and grows smoothly as $M_{\mathrm{PS}}/M_{\mathrm{V}}$ decreases.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·20 citations
4. 04*

   Glueballs and topology with O(a)-improved lattice QCD

   A. Hart (DAMTP, Cambridge)🇬🇧

   We present evidence for unquenching effects in N_f=2, 16^3 32 ensembles by comparing with `equivalent' quenched data at r_0~5.0. A (small) VEV for torelons signals (weak) string breaking. A 15-20 % reduction in the scalar glueball mass relative to quenched is argued to be (in part at least) a discretisation effect. We find a chiral suppression of the topological susceptibility consistent with expectations, and agreement between fermionic and gluonic methods for measuring the topological charge.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·5 citations
5. 05*

   The Static Potential with Hypercubic Blocking

   A. Hasenfratz (U. of Colorado)🇺🇸 · R. Hoffmann (U. Regensburg)🇺🇸 · F. Knechtli (HU Berlin)🇺🇸

   We measure the static potential from Wilson loops constructed using hypercubic blocked (HYP) links. The HYP potential agrees with the potential measured using thin links for distances r/a>=2. We calculated the lowest order perturbative expansion of the lattice Coulomb potential of HYP links. These results are used in analyzing the static potential both on quenched and dynamical lattices. The statistical accuracy of the potential with HYP links improves by about an order of magnitude, giving a reliable scale even with limited statistics both on quenched and dynamical lattices.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·86 citations
6. 06*

   Extraction of K-->pipi Matrix Elements with Wilson Fermions

   Ph.Boucaud🇫🇷 · V.Gimenez🇪🇸 · C.J.D.Lin🇬🇧 · V.Lubicz🇮🇹 · G.Martinelli🇮🇹 · M.Papinutto🇮🇹 · F.Rapuano🇮🇹 · C.T.Sachrajda: S.P.Qcd R. collaboration🇬🇧

   We present the status of a lattice calculation for the K-->pipi matrix elements of the (delta S=1) effective weak Hamiltonian, directly with two pion in the final state. We study the energy shift of two pion in a finite volume both in the I=0 and I=2 channels. We explain a method to avoid the Goldstone pole contamination in the computation of renormalization constants for (delta I=3/2) operators. Finally we show some preliminary results for the matrix elements of (delta I=1/2) operators. Our quenched simulation is done at beta=6.0, with Wilson fermions, on a (24^3 X 64) lattice.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·17 citations
7. 07*

   Finite-volume meson propagators in quenched chiral perturbation theory

   P.H. Damgaard🇨🇭 · M.C. Diamantini🇨🇭 · P. Hernandez🇨🇭 · K. Jansen🇩🇪

   We compute meson propagators in finite-volume quenched chiral perturbation theory.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·2 citations
8. 08*

   Anisotropic Lattices and Dynamical Fermions

   L. Levkova🇺🇸 · T. Manke🇺🇸

   We report results from full QCD calculations with two flavors of dynamical staggered fermions on anisotropic lattices. The physical anisotropy as determined from spatial and temporal masses, their corresponding dispersion relations, and spatial and temporal Wilson loops is studied as a function of the bare gauge anisotropy and the bare velocity of light appearing in the Dirac operator. The anisotropy dependence of staggered fermion flavor symmetry breaking is also examined. These results will then be applied to the study of 2-flavor QCD thermodynamics.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·6 citations
9. 09*

   Staggered domain wall fermions

   G. T. Fleming🇺🇸 · P. M. Vranas🇺🇸

   Staggered Domain Wall Fermions (SDWF) combine the attractive chiral properties of staggered fermions with those of domain wall fermions. SDWF describe four flavors with exact U(1)xU(1) flavor chiral symmetry. An extra lattice dimension is introduced and the full SU(4)xSU(4) flavor chiral symmetry is recovered as its size is increased. Here, the free theory of SDWF is described and a preliminary discussion of the interacting case is presented. SDWF may be well suited for numerical simulation of lattice QCD thermodynamics.

   hep-latNucl.Phys.B Proc.Suppl.(2002)·2 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.