Mon·Sep 15, 2003Monday·September 15, 2003

1. 01*

   Fractal Structure of 4D Euclidean Simplicial Manifold

   H. S. Egawa🇯🇵 · S. Horata🇯🇵 · T. Yukawa🇯🇵

   The fractal properties of four-dimensional Euclidean simplicial manifold generated by the dynamical triangulation are analyzed on the geodesic distance D between two vertices instead of the usual scale between two simplices. In order to make more unambiguous measurement of the fractal dimension, we employ a different approach from usual, by measuring the box-counting dimension which is computed by counting the number of spheres with the radius D within the manifold. The numerical result is consistent to the result of the random walk model in the branched polymer region. We also measure the box-counting dimension of the manifold with additional matter fields. Numerical results suggest that the fractal dimension takes value of slightly more than 4 near the critical point. Furthermore, we analyze the correlation functions as functions of the geodesic distance. Numerically, it is suggested that the fractal structure of four-dimensional simplicial manifold can be properly analyzed in terms of the distance between two vertices. Moreover, we show that the behavior of the correlation length regards the phase structure of 4D simplicial manifold.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·5 citations
2. 02*

   Lattice study on kaon nucleon scattering length in the I=1 channel

   Guangwei Meng🇨🇳 · Chuan Miao🇨🇳 · Xining Du🇨🇳 · Chuan Liu🇨🇳

   Using the tadpole improved clover Wilson quark action on small, coarse and anisotropic lattices, $KN$ scattering length in the I=1 channel is calculated within quenched approximation. The results are extrapolated towards the chiral and physical kaon mass region. Finite volume and finite lattice spacing errors are also analyzed and a result in the infinite volume and continuum limit is obtained which is compatible with the experiment and the results from Chiral Perturbation Theory.

   hep-lathep-phnucl-thInt.J.Mod.Phys.A(2004)·31 citations
3. 03*

   $q\bar{q}$ and $2q2\bar{q}$ systems in terms of P-vortices

   V.G. Bornyakov🇷🇺 · A.V. Kovalenko🇷🇺 · M.I. Polikarpov🇷🇺 · D.A. Sigaev🇷🇺

   We study the action and the energy densities of the confining string in the indirect Z(2) projection of SU(2) lattice gauge theory. We find that the width of the confining string is proportional to the logarithm of the distance between the quark and antiquark. In $2q2\bar{q}$ system we observe the effect of the reconstruction of the flux tube when we change the distance between two $q\bar{q}$ pairs.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·5 citations
4. 04*

   Indications on the Higgs boson mass from lattice simulations

   P. Cea🇮🇹 · M. Consoli🇮🇹 · L. Cosmai🇮🇹

   The `triviality' of ${\Phi }_4^4$ has been traditionally interpreted within perturbation theory where the prediction for the Higgs boson mass depends on the magnitude of the ultraviolet cutoff $\Lambda$. This approach crucially assumes that the vacuum field and its quantum fluctuations rescale in the same way. The results of the present lattice simulation, confirming previous numerical indications, show that this assumption is not true. As a consequence, large values of the Higgs mass $m_H$ can coexist with the limit $\Lambda \to \infty$. As an example, by extrapolating to the Standard Model our results obtained in the Ising limit of the one-component theory, one can obtain a value as large as $m_H=760\pm 21$ GeV, independently of $\Lambda$.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·13 citations
5. 05*

   Simulations in the epsilon-Regime of Chiral Perturbation Theory

   K.-I. Nagai🇩🇪 · W. Bietenholz🇩🇪 · T. Chiarappa🇩🇪 · K. Jansen🇩🇪 · S. Shcheredin🇩🇪

   We discuss the potential of Ginsparg-Wilson fermion simulations in the epsilon-regime of chiral perturbation theory, regarding the determination of the leading low energy constants of the effective chiral Lagrangian. It turns out to be very hard to measure observables in the topologically trivial sector. There a huge statistics would be required, due to the frequent occurrence of very small eigenvalues. Moreover, contact with chiral perturbation theory is only established if the physical volume of the system is sufficiently large.

   hep-lathep-phNucl.Phys.B Proc.Suppl.(2004)·9 citations
6. 06*

   Comparison of analytic and numerical results in the XY-model

   J. Balog🇭🇺 · F. Knechtli🇩🇪 · T. Korzec🇩🇪 · U. Wolff🇩🇪

   We study the two dimensional XY-model with high precision Monte Carlo techniques and investigate the continuum approach of the step-scaling function of its finite volume mass gap. The continuum extrapolated results are found consistent with analytic predictions for the finite volume energy spectrum based on the equivalence with sine-Gordon theory. To come to this conclusion it was essential to use an also predicted form of logarithmic decay of lattice artifacts for the extrapolation.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·0 citations
7. 07*

   An analysis of the vector meson spectrum from lattice QCD

   W. Armour🇬🇧

   We re-analyse meson sector data from the CP-PACS collaboration's dynamical simulations. Our analysis uses several different approaches, and compares the standard naive linear fit with the Adelaide Anzatz. We find that setting the scale using the J parameter gives remarkable agreement among data sets. Our predictions for the rho and phi masses have very small statistical errors, ~ 3 MeV, but the discrepancy between the different fitting approaches is ~ 40 MeV.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·0 citations
8. 08*

   The two-dimensional Wess-Zumino model in the Hamiltonian lattice formulation

   Matteo Beccaria🇮🇹 · Massimo Campostrini🇮🇹 · Alessandra Feo🇮🇪

   We investigate a Hamiltonian lattice version of the two-dimensional Wess-Zumino model, with special emphasis to the pattern of supersymmetry breaking. Results are obtained by Quantum Monte Carlo simulations and Density Matrix Renormalization group techniques.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·7 citations
9. 09*

   Quark Loop Effects in Semileptonic Form Factors for Heavy-Light Mesons

   C. Bernard (1)🇺🇸 · C. DeTar (2)🇺🇸 · Steven Gottlieb (3)🇺🇸 · E. Gregory (4)🇺🇸 · Urs Heller (5)🇺🇸 · C. McNeile (6)🇬🇧 · J. Osborn (2)🇺🇸 · R. Sugar (7)🇺🇸 · D. Toussaint (4) ((1) Wash. U., (2) U. Utah, (3) Indiana U., (4) U. Arizona, (5) APS, (6) U. Liverpool, (7) UCSB)🇺🇸

   We present preliminary results of a determination of the semileptonic form factor for the decay of pseudoscalar heavy-light mesons to pseudoscalar light-light mesons in full QCD. In this preliminary study we focus on the effects of dynamical quark loops. Accordingly, we compare results of simulations with matched quenched and Asqtad dynamical gauge configurations. The latter include three flavors of light quarks. Our simulation uses clover Wilson valence quarks, treated in the Fermilab formalism. Preliminary results, as yet uncorrected by continuum matching factors, suggest a measurable enhancement in the form factor due to dynamical quark loops over the accessible range of $q^2$.

   hep-latNucl.Phys.B Proc.Suppl.(2004)·6 citations
10. 10*

    The long range properties of the compact U(1) lattice gauge theory with the multi-level algorithm

    Y. Koma🇩🇪 · M. Koma🇩🇪 · P. Majumdar🇩🇪

    The 4D compact U(1) lattice gauge theory (LGT) in the confinement phase is studied with the multi-level algorithm. The static potential, force and flux-tube profile between two static charges are precisely measured from correlation functions involving the Polyakov loop. Universality of the coefficient of the 1/r correction to the static potential, known as the Luescher term, and the transversal width of the flux-tube profile are investigated.

    hep-latNucl.Phys.B Proc.Suppl.(2004)·1 citation
11. 11*

    A numerical reinvestigation of the Aoki phase with N_f=2 Wilson fermions at zero temperature

    E.-M. Ilgenfritz🇩🇪 · W. Kerler🇩🇪 · M. Mueller-Preussker🇩🇪 · A. Sternbeck🇩🇪 · H. Stueben🇩🇪

    We report on a numerical reinvestigation of the Aoki phase in lattice QCD with two flavors of Wilson fermions where the parity-flavor symmetry is spontaneously broken. For this purpose an explicitly symmetry-breaking source term $h\bar{\psi }i{\gamma }_5{\tau }^3\psi$ was added to the fermion action. The order parameter $<\bar{\psi }i{\gamma }_5{\tau }^3\psi >$ was computed with the Hybrid Monte Carlo algorithm at several values of $(\beta ,\kappa ,h)$ on lattices of sizes $4^4$ to $12^4$ and extrapolated to $h=0$. The existence of a parity-flavor breaking phase can be confirmed at $\beta =4.0$ and 4.3, while we do not find parity-flavor breaking at $\beta =4.6$ and 5.0.

    hep-latPRD(2004)·48 citations
12. 12*

    The 2+2 anisotropic Wilson gluon action with applications

    Giuseppe Burgio🇮🇪 · Alessandra Feo🇮🇪 · Mike Peardon🇮🇪 · Sinead M. Ryan🇮🇪

    A generalization of anisotropic lattices to include a 2+2 discretization is discussed. As a part of this program, we determine the one-loop correction to the gluon self-energy and analyse the restoration of Lorentz invariance in on-shell states for both the 2+2 and 3+1 cases. A 2+2 Wilson-like fermion action is also considered.

    hep-latNucl.Phys.B Proc.Suppl.(2004)·1 citation
13. 13*

    The Aoki phase for N_f=2 Wilson fermions revisited

    A. Sternbeck🇩🇪 · E.-M. Ilgenfritz🇩🇪 · W. Kerler🇩🇪 · M. Mueller-Preussker🇩🇪 · H. Stueben🇩🇪

    We report on a numerical reinvestigation of the Aoki phase in full lattice QCD with two flavors of unimproved Wilson fermions. For zero temperature the Aoki phase can be confirmed at inverse coupling $\beta =4.0$ and $\beta =4.3$, but not at $\beta =4.6$ and $\beta =5.0$. At non-zero temperature the Aoki phase was found to exist also at $\beta =4.6$.

    hep-latNucl.Phys.B Proc.Suppl.(2004)·15 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.