The glueball-to-vacuum matrix elements of local gluonic operators in scalar, tensor, and pseudoscalar channels are investigated numerically on several anisotropic lattices with the spatial lattice spacing ranging from 0.1fm -0.2fm. These matrix elements are needed to predict the glueball branching ratios in J/ψ radiative decays which will help identify the glueball states in experiments. Two types of improved local gluonic operators are constructed for a self-consistent check and the finite volume effects are studied. We find that lattice spacing dependence of our results is very weak and the continuum limits are reliably extrapolated, as a result of improvement of the lattice gauge action and local operators. We also give updated glueball masses with various quantum numbers.

Chiral perturbation theory is applied to the decay K -+ 2~. It is shown that, to quadratic order in meson masses, the amplitude for K-+27r can be written in terms of the unphysical amplitudes K -m and K-0, where 0 is the vacuum. One may then hope to calculate these two simpler amplitudes with lattice Monte Carlo techniques, and thereby gain understanding of the AI = rule in K decay. The reason for the presence of the K-iO amplitude is explained: it serves to cancel off unwanted renormalization contributions to K-T.We make a rough test of the practicability of these ideas in Monte Carlo studies. We also describe a method for evaluating meson decay constants which does not require a determination of the quark masses.

A numerical simulation of quenched QCD on a 24 X 12 X 12 X 24 lattice at /3= 5.9 is used to calculate the electric and magnetic form factors of the baryon octet. General forms of the baryon interpolating fields are considered. Magnetic moments, electric radii, magnetic radii, and magnetic transition moments are extracted from the form factors. The electric properties are found to be consistent with a quark-model picture involving spin-dependent forces. The lattice results for the magnetic properties show a mass and spin dependence of the effective quark moments which is not accounted for in conventional quark models. Lattice calculations underestimate the magnitude of electric radii, magnetic radii, and magnetic moments compared to experimental measurements. The finite volume of the periodic lattice may be responsible for the discrepancies. The pattern of electromagnetic radii in the lattice results are seen to be generally reproduced in the model results that are considered. The only exception is that of Z-which proves to be a sensitive probe of the quark dynamics. Lattice calculations indicate a positive value for the normalized square magnetic radius in Z-which contrasts Skyrme model results. Ratios of the magnetic moments allow a more detailed comparison with the experimental measurements. The lattice calculations are seen to better reproduce the experimental ratios than the model calculations.

The electromagnetic properties of the SU (3)-flavor baryon decuplet are examined within a lattice simulation of quenched QCD. Electric charge radii, magnetic moments, and magnetic radii are extracted from the E0 and M 1 form factors. Preliminary results for the E2 and M 3 moments are presented giving the first model independent insight to the shape of the quark distribution in the baryon ground state. As in our octet baryon analysis, the lattice results give evidence of spin-dependent forces and mass effects in the electromagnetic properties. The quark charge distribution radii indicate these effects act in opposing directions. Some baryon dependence of the effective quark magnetic moments is seen. However, this dependence in decuplet baryons is more subtle than that for octet baryons. Of particular interest are the lattice predictions for the magnetic moments of Ω − and ∆ ++ for which new recent experimental measurements are available. The lattice prediction of the ∆ ++ /p ratio appears larger than the experimental ratio, while the lattice prediction for the Ω − /p magnetic moment ratio is in good agreement with the experimental ratio.

Low-dimensional long-range topological charge structure in the QCD vacuum Physical

We report results on the proton mass decomposition and also on related quark and glue momentum fractions. The results are based on overlap valence fermions on four ensembles of N f = 2 + 1 DWF configurations with three lattice spacings and three volumes, and several pion masses including the physical pion mass. With fully non-perturbative renormalization (and universal normalization on both quark and gluon), we find that the quark energy and glue field energy contribute 33(4)(4)% and 37(5)(4)% respectively in the M S scheme at µ = 2 GeV. A quarter of the trace anomaly gives a 23 (1)(1)% contribution to the proton mass based on the sum rule, given 9(2)(1)% contribution from the u, d, and s quark scalar condensates. The u, d, s and glue momentum fractions in the M S scheme are in good agreement with global analyses at µ = 2 GeV.Introduction: In the standard model, Higgs boson provides the origin of quark masses. But how it is related to the proton mass and thus the masses of nuclei and atoms is another question. The masses of the valence quarks in the proton are just ∼3 MeV per quark which is directly related to the Higgs boson, while the total proton mass is 938 MeV. The percentage of the quark and gluon contributions to the proton mass can only be provided by solving QCD non-perturbatively, and/or with information from experiment. With phenomenological input, the first decomposition was carried out by Ji [1]. As in Refs. [1,2], the Hamiltonian of QCD can be decomposed asin the rest frame of the hadron state where M is the hadron mass, T µν is the energy momentum tensor of QCD with T 44 as its expectation value in the hadron, and the trace anomaly gives

The electromagnetic transition moments of the SU(3)avor baryon octet to decuplet are examined within a lattice simulation of quenched QCD.The magnetic transition moment for the N $ channel is found to be in agreement with recent experimental analyses. The lattice results indicate p = p = 0:88(15). In terms of the Particle Data Group convention, f M1 = 0:231(41) GeV 1=2 for p $ + transitions. Lattice predictions for the hyperon M1 transition moments agree with those of a simple quark model. However the manner in which the quarks contribute to the transition moments in the lattice simulation is di erent from that anticipated by quark model calculations. The scalar quadrupole form factor exhibits a behavior consistent with previous multipole analyses. The E2=M1 multipole transition moment ratios are also determined. The lattice results suggest

Lattice QCD calculations with chiral fermions of the πN sigma term σπN and strangeness sigma term σsN including chiral interpolation with continuum and volume corrections are provided in this work, with the excited-state contaminations subtracted properly. We calculate the scalar matrix element for the light/strange quark directly and find σπN = 45.9(7.4)(2.8) MeV, with the disconnected insertion part contributing 20(12)(4)%, and σsN = 40.2(11.7)(3.5) MeV, which is somewhat smaller than σπN . The ratio of the strange/light scalar matrix elements is y = 0.09(3)(1).