Related papers: Scalar mesons in a finite volume
We carry out an exploratory study of the isospin one a0(980) and the isospin one-half kappa scalar mesons using Nf=2+1+1 Wilson twisted mass fermions at one lattice spacing. The valence strange quark is included as an Osterwalder-Seiler…
In the past year domain wall fermion simulations have moved from exploratory stages to the point where systematic effects can be studied with different gauge couplings, volumes, and lengths in the fifth dimension. Results are presented here…
In a finite volume, resonances and multi-hadron states are identified by discrete energy levels. When comparing the results of lattice QCD calculations to scattering experiments, it is important to have a way of associating the energy…
Lattice quantum chromodynamics (QCD) will soon become the primary theoretical tool in rigorous studies of single- and multi-hadron sectors of QCD. It is truly ab initio meaning that its only parameters are those of standard model. The…
We investigate the structure of the scalar mesons $f_0(975)$ and $a_0(980)$ within realistic meson-exchange models of the $\pi\pi$ and $\pi\eta$ interactions. Starting from a modified version of the J\"ulich model for $\pi\pi$ scattering we…
We analyse the meson spectrum in quenched QCD using lattice gauge theory. By studying hadron propagation with a variety of operators (both smeared and local), we are able to extract the ground state and first excited state masses with…
The structure of the scalar mesons has been a subject of debate for many decades. In this work we look for $\bar{q}q$ states among the physical resonances using an extended Linear Sigma Model that contains scalar, pseudoscalar, vector, and…
A phenomenological analysis of the scalar meson f0(980) is performed that relies on the quasi-two body decays D and Ds -> f0(980)P, with P=pi, K. The two-body branching ratios are deduced from experimental data on D or Ds -> pi pi pi, K…
The signature of bound state formation on the lattice is of particular interest in this talk. In the finite volume, where all states have discrete energies, it is rather hard to distinguish between a bound state and a scattering state if…
We present a calculation of the meson masses, decay constants and quark-antiquark vacuum expectation value for the three generic QCD-like chiral symmetry breaking patterns $SU(N_F)\times SU(N_F)\to SU(N_F)_V$, $SU(N_F)\to SO(N_F)$ and…
We review the analysis of the quark and gluon substructures of the scalar mesons from QCD spectral sum rules and some low-energy theorems applied to the scalar QCD anomaly current. The present data favour equal components of \bar uu+ \bar…
The Chiral Confining Lagrangian, based on the chiral theory with quark degrees of freedom, is used to study the spectroscopy of scalar mesons. The formalism does not contain arbitrary fitting parameters and takes into account infinite…
The different ground state energies of N-pion and M-kaon systems for N+M <=12 are studied in lattice QCD. These energies are then used to extract the various two- and three- body interactions that occur in these systems. Particular…
Our progress in computing the spectrum of excited baryons and mesons in lattice QCD is described. Sets of spatially-extended hadron operators with a variety of different momenta are used. A new method of stochastically estimating the…
We use chiral perturbation theory to study the extrapolations necessary to make physical predictions from lattice QCD data for the electromagnetic form factors of pseudoscalar mesons. We focus on the quark mass, momentum, lattice spacing,…
Lattice QCD can give direct information on OZI-violating contributions to mesons. Here we explore the contributions that split flavour singlet and non-singlet meson masses. I discuss in detail the spectrum and decays for scalar mesons (ie…
It has been known for a long time that the large experimental singlet-octet mass gap in the pseudoscalar meson mass spectrum originates from the anomaly of the axial vector current, i.e. from nonperturbative effects and the nontrivial…
For quantifying the universal properties of the chiral phase transition in QCD through numerical calculations on a discrete space-time lattice, one needs to perform controlled extrapolations to the continuum and infinite-volume limits…
Masses and widths of the four light scalar mesons $\sigma$, $\kappa$, $a_0$(980) and $f_0$(980) may be reproduced in a model where mesons scatter via a $q\bar{q}$ loop. A transition potential is used to couple mesons to $q\bar{q}$ at a…
We present a study of {\it finite} $a$ and {\it volume} effects of the leptonic decay constant $f$ of heavy pseudoscalar mesons in the static approximation. This study is performed on a number of lattices at $\beta=$ 5.74,~6.0 and 6.26…