Chiral symmetry properties, scaling, and finite volume effects of the overlap fermions are studied numerically on 3 small lattices and 3 couplings. Results on hadron masses and quark condensates will be given. Preliminary results on large physical volume will also be presented.
Authors:K.F. Liu, S.J. Dong, F.X. Lee, and J.B. Zhang
Proposed speaker: Keh-Fei Liu
Contact person:Keh-Fei Liu
(University of Kentucky),
liu@pa.uky.edu
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers:
Notes:
A disorder parameter detecting monopole condensation in the ground state of QCD is studied on the lattice for full QCD. We obtain evidence that the mechanism of confinement is dual superconductivity ,as for pure gauge theory. Contrary to the familiar parameters (Polyakov line ,chiral condensate) our disorder parameter is the same for quenched and unquenched theory.The presence of quarks is marginal, in agreement with the idea that the structure of the theory is Nc independent at large Nc.
Authors:Adriano Di Giacomo
Proposed speaker: J.Carmona,M.D'Elia,Adriano Di Giacomo,,B.Lucini
Contact person:Adriano Di Giacomo
(PISA UNIVERSITY),
adriano.digiacomo@df.unipi.it
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: A.Di Giacomo et al Phys Rev D61 034503,034504 2000 J.Carmona et al hep-lat/0003002
Notes:
Noncompact U(1) chiral gauge theories are defined on the lattice in the overlap formalism in any even Euclidean dimension. If anomalies cancel at one-loop perturbation theory gauge invariance can be made exact outside perturbation theory. If anomalies do not cancel, the gauge violation can be brought to a standard form. The distinction between the anomalous and non-anomalous cases in four space-time dimensions is explained. Although in both cases one cannot remove the cutoff fully, the dependence on the cutoff is different.
Authors:H. Neuberger
Proposed speaker: H. Neuberger
Contact person:Herbert Neuberger
(Rutgers University),
neuberg@physics.rutgers.edu
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: Noncompact chiral U(1) gauge theories on the lattice. H. Neuberger. hep-lat/0002032.
Notes:
The first test of the Kugo-Ojima colour confinement criterion by the lattice Landau gauge QCD simulation is performed. The parameter $u^{ab}$ which is expected to be $-1\delta^{ab}$ for the confinement is found to be $-0.7\delta^{ab}$ in the strong coupling region, $\beta=5.5$, and its magnitude is close to 0.7 but slightly smaller in the weak coupling region, $\beta=6.0$, in $16^4$ lattice simulation. The simulation data are analysed also for the test of Zwanziger's theory developed for the Gribov problem in use of the horizon function, and discussions are given on the Gribov-Zwanziger theory including a critical comment on the justification of the formulation.
Authors:Hideo Nakajima, Sadataka Furui, Azusa Yamaguchi
Proposed speaker: Hideo Nakajima
Contact person:Hideo Nakajima
(Utsunomiya University),
nakajima@is.utsunomiya-u.ac.jp
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: H. Nakajima, S. Furui, Lattice 99 Proceedings, hep-lat/9909008, QNP2000 Proceedings, hep-lat/0004023.
Notes:
Results of a systematic lattice QCD simulation with two flavors dynamical quarks are presented. Clear dynamical quark effects are observed in the light hadron mass spectrum, light quark masses, B meson decay constants, etc. In the light hadron mass spectrum, major parts of the discrepancy between quenched QCD and experiment are shown to be removed by two flavors of dynamical quarks. For the averaged mass of $u$, and $d$ quarks, we find $m_{ud}^{\bar{\rm MS}}(2GeV) = 3.5 \pm 0.3$ MeV, while for the $s$ quark mass, $m_{s}^{\bar{\rm MS}}(2GeV) = 90$--100 MeV. These vales are about 20--30\% smaller than previous estimates in the quenched approximation.
Authors:CP-PACS Collaboration
Proposed speaker: Kazuyuki Kanaya
Contact person:Kazuyuki Kanaya
(Univ. of Tsukuba),
kanaya@rccp.tsukuba.ac.jp
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers:
Notes:
We present lattice calculations of the gluon and quark propagators in Landau gauge in (quenched) QCD. For the gluon propogator both unimproved and order a^2 improved calculations on large volumes will be presented. We see strong evidence that the Landau gauge gluon propagator is infrared finite. At large momenta we observe the transition to perturbative behavior. Similar results are presented for the quark propagator with order a improvement. The dynamically generated infrared quark mass is clearly observed and found to be approximately 300MeV. The method for removing the dominant, tree-level lattice artefacts in these studies will be presented.
Authors:A.G. Williams
Proposed speaker: A.G. Williams
Contact person:Anthony G Williams
(University of Adelaide),
awilliam@physics.adelaide.edu.au
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: INFRARED BEHAVIOR OF THE GLUON PROPAGATOR ON A LARGE VOLUME LATTICE. By Frederic D.R. Bonnet, Patrick O. Bowman, Derek B. Leinweber, Anthony G. Williams (Adelaide U., CSSM & Adelaide U.). ADP-00-10-T396, Feb 2000. 8pp. e-Print Archive: hep-lat/0002020 THE QUARK PROPAGATOR IN MOMENTUM SPACE. By Jon Ivar Skullerud, Anthony G. Williams (Adelaide U.). Jun 1999. 3pp. e-Print Archive: hep-lat/9909142 IMPROVED LANDAU GAUGE FIXING AND DISCRETIZATION ERRORS. By F.D.R. Bonnet, P.O. Bowman, D.B. Leinweber (Adelaide U.), D.G. Richards (Edinburgh U. & Jefferson Lab), A.G. Williams (Adelaide U. & Florida State U. & Florida State U., CSIT). Jun 1999. 3pp. Talk given at 17th International Symposium on Lattice Field Theory (LATTICE 99), Pisa, Italy, 29 Jun - 3 Jul 1999. e-Print Archive: hep-lat/9909110 ASYMPTOTIC SCALING AND INFRARED BEHAVIOR OF THE GLUON PROPAGATOR. By UKQCD Collaboration (Derek B. Leinweber et al.). ADP-98-72-T339, Nov 1998. 35pp. Published in Phys.Rev.D60:094507,1999, Erratum-ibid.D61:079901,2000 e-Print Archive: hep-lat/9811027
Notes:I have been invited to attend ICHEP already and so it would be most helpful if this talk is selected for presentation.
A short survey of non-perturbative renormalization by means of numerical simulations in lattice field theory, with emphasis on some recent developments in applications to phenomenologically relevant quantities, is given. As an illustrative example I sketch the general concepts and a strategy for the determination of quark masses. Following these lines, results from a computation of the renormalization group invariant strange quark mass in the quenched approximation of QCD by the ALPHA and UKQCD Collaborations are presented and confronted with those of other approaches.
Authors:ALPHA Collaboration
Proposed speaker: Jochen Heitger
Contact person:Jochen Heitger
(DESY Zeuthen),
heitger@ifh.de
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers:
Notes:
The talk will consist in an overview of the subject, addressed also to non specialists.
Authors:M. Testa
Proposed speaker: M. Testa
Contact person:Massimo Testa
(Universita' degli Studi "La Sapienza"),
massimo.testa@roma1.infn.it
Sessions: PA-14 Lattice Field Theory /
Supporting papers:
Notes:
We compute the average momentum of a parton for a pion matrix element in the quenched approximation. The renormalization is performed fully non-perturbatively using the Schroedinger functional scheme and a careful continuum extrapolation is done. We compare the result, obtained in the MSbar scheme, with other approaches in the literature.
Authors:A. Bucarelli, M. Guagnelli, K. Jansen, F. Palombi, R. Petronzio, A. Shindler
Proposed speaker: M. Guagnelli
Contact person:Marco Guagnelli
(Universita' di Tor Vergata),
marco.guagnelli@roma2.infn.it
Sessions: PA-14 Lattice Field Theory /
Supporting papers: A. Bucarelli et al, Nucl.Phys. B552 (1999) 379-391 M. Guagnelli et al, Nucl.Phys. B542 (1999) 395-409 M. Guagnelli et al, Phys.Lett. B457 (1999) 153-156 M. Guagnelli et al, Phys.Lett. B459 (1999) 594-598
Notes:
We discuss the structure of domain wall fermion in relation to the exact chiral symmetry based on the Ginsparg-Wilson relation. In domain wall QCD, quark fields on the boundary walls are indeed described by the effective four-dimensional Dirac operator which satisfies the Ginsparg-Wilson relation. In chiral case when the domain wall fermion couples to an interpolating five-dimensional gauge field, it can be regarded as a lattice implementation of the the eta-invariant and the effective action for chiral Ginsparg-Wilson fermions is reproduced by including a five-dimensional lattice Chern-Simons term.
Authors:Yoshio Kikukawa
Proposed speaker: Yoshio Kikukawa
Contact person:Yoshio Kikukawa
(Nagoya Univ.),
kikukawa@eken.phys.nagoya-u.ac.jp
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: Y. Kikukawa and T. Noguchi, hep-lat/902022, T. Aoyama and Y. Kikukawa, hep-lat/9905003, Y. Kikukawa, hep-lat/9912056
Notes:
Computational and theoretical developments in lattice QCD calculations of $B$ and $D$ mesons are surveyed. Several topical examples are given: decay constants ($f_B$, $f_{D_s}$, etc.); form factors needed to determine $|V_{cb}|$ and $|V_{ub}|$; bag parameters for the mass and width differences of the $B$ mesons; and new ideas for calculating the HQET parameters $\bar{\Lambda}$ and $\lambda_1$. Prospects for removing the uncertainties from the ``quenched approximation'' are discussed.
Authors:Andreas S. Kronfeld
Proposed speaker: Andreas S. Kronfeld
Contact person:Andreas S Kronfeld
(Fermi National Accelerator Laboratory),
ask@fnal.gov
Sessions: PA-14 Lattice Field Theory / PL-05 Lattice Field Theory
Supporting papers: hep-lat/0002008, hep-lat/9910026, hep-lat/9910010, hep-ph/9906376
Notes:The talk is a mini-review solicited by conveners Tetsuya Onogi and Karl Jansen. The abstract is late, because some technicalities had to be clarified.
End of abstracts for PA-14 Lattice Field Theory