Related papers: Approximating chiral SU(3) amplitudes
Using recent precise hadronic tau-decay data on the V-A spectral function and general properties of QCD such as analyticity, the operator product expansion and chiral perturbation theory, we get accurate values for the QCD chiral order…
We argue that the difficulties associated with the convergence properties of conventional SU(3) chiral perturbation theory can be ameliorated by use of a cutoff, which suppresses the model-dependent short distance effects in such…
In this paper bounds for L_1, L_2 and L_3 are obtained in Chiral Perturbation Theory with three flavours. At the same time we test the compatibility of this theory with axiomatic principles. Following a recent paper we use dispersion…
A high precision determination of the strong coupling constant in the MS-bar scheme at the Z-mass scale, using low energy quantities, namely pion/kaon decay constants and masses, as experimental input is presented. The computation employs…
We have performed numerical simulations of SU(3) gauge theory coupled to Nf=2 flavors of symmetric representation fermions. The fermions are discretized with the tadpole-improved clover action. Our simulations are done on lattices of length…
We review the theory that predicts that the decay constant of the excited light pseudo-scalar mesons are suppressed in the chiral limit relative to the pion decay constant. We compute the decay constant of the first excited pion…
We study the SU(3) gauge theory with Nf=12 flavors in the fundamental representation by use of lattice simulations with staggered fermions. With a non-improved action we observe a chiral zero-temperature (bulk) transition separating a…
We determine the masses and pseudoscalar decay constants of D and D_s mesons employing lattice QCD with non-perturbatively O(a) improved Wilson quarks and a tree-level Symanzik-improved gauge action. Our analysis is based on the…
We consider lattice gauge theories at strong coupling with gauge group $U(N_C)$, or $SU(N_C)$ restricted to the meson sector, and coupled to $N_F$ flavors of fundamental representation staggered fermions. We study the formation of a chiral…
We explore a method developed in statistical physics which has been argued to have exponentially small finite-volume effects, in order to determine the critical temperature Tc of pure SU(3) gauge theory close to the continuum limit. The…
In the framework of the instanton vacuum model we make expansion over the current mass $m$ and number of colors $N_c$ and evaluate ${\cal O}(1/N_c, m, m/N_c, m \ln m/N_c)$-corrections to the dynamical quark mass $M$, the quark condensate…
In the chiral limit of QCD, the pion decay constant F can be extracted from lattice gauge theory by means of a coupling to isospin chemical potential. Here we compute the leading correction due to finite volume in the epsilon-expansion of…
We present the first quenched lattice QCD study of the form factors relevant for the hyperon semileptonic decay Sigma -> n l nu. The momentum dependence of both axial and vector form factors is investigated and the values of all the form…
Remarkably accurate fine structure constants are calculated from assumptions further developed from two earlier publications. We have put together a series of energy scales related to various physical phenomena such as the Planck scale, a…
The progress in determining the coupling constants of mesonic chiral Lagrangians is reviewed, with emphasis on the work performed in three successive European Networks (Eurodaphne I and II, Euridice). Reliable estimates of those constants…
We determine the masses and decay constants of pseudoscalar mesons $ D $, $ D_s $, and $ K $ in quenched lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with single-plaquette action at $ \beta = 6.1 $ on the $…
We analyze the properties of four-quark condensates and scalar susceptibilities in the meson gas, within finite temperature Chiral Perturbation Theory (ChPT). The breaking of the factorization hypothesis does not allow for a finite…
We compute decay constants of heavy-light mesons in quenched lattice QCD with a lattice spacing of a ~ 0.04 fm using non-perturbatively O(a) improved Wilson fermions and O(a) improved currents. We obtain f_{D_s} = 220(6)(5)(11) MeV, f_D =…
We study the scaling properties of the static quark potential and the ratio of the critical temperature $T_c$ to the square root of the string tension $\sigma$ in the SU(3) pure gauge theory using a renormalization group improved action. We…
Finite size scaling is a powerful tool to study the critical properties of systems governed by one relevant operator, assuming all irrelevant operators have scaling dimensions much smaller then zero. This condition is likely not satisfied…