Related papers: Bubble contributions to scalar correlators with mi…
We provide the analytic predictions for the flavor non-singlet scalar correlator, which will enable determination of the scalar meson mass from the lattice scalar correlator. We consider simulations with 2+1 staggered sea quarks and…
We determine the mass of the lightest quark-antiquark scalar meson with I=1 using the simulation with two dynamical Domain Wall Fermions. The conventional exponential fit of the scalar correlator is justified in this case giving the mass…
We study the $\kappa$ meson in 2+1 flavor QCD with sufficiently light $u/d$ quarks. Using numerical simulation we measure the point-to-point $\kappa$ correlators in the "Asqtad" improved staggered fermion formulation. We analyze those…
We present a study of the pseudoscalar propagator in the mixed chiral regime with valence quark masses in the \epsilon-regime and sea quark masses in the p-regime. We first show the NNLO prediction of this observable in the chiral…
We investigate effects resulting from the use of different discretizations for the valence and the sea quarks in lattice QCD, considering Wilson and/or Ginsparg-Wilson fermions. We assume that such effects appear through scaling violations…
We extend chiral perturbation theory to include linear dependence on the lattice spacing $a$ for the Wilson action. The perturbation theory is written as a double expansion in the small quark mass $m_q$ and lattice spacing $a$. We present…
We study discretization effects in a mixed-action lattice theory with domain-wall valence quarks and Asqtad-improved staggered sea quarks. At the level of the chiral effective Lagrangian, discretization effects in the mixed-action theory…
We consider effects resulting from the use of different discretizations for the valence and the sea quarks, considering Wilson and/or Ginsparg--Wilson fermions. We assume that such effects appear through scaling violations that can be…
Higher order effects of the two-dimensional non-Abelian gauge theories, in which the vector-meson mass is generated by chiral anomalies, will be studied. The $\beta$ function and the topological nature of the non-linear $\sigma$ model in…
We present a comprehensive analysis of form factors for two light pseudoscalar mesons induced by scalar, vector, and tensor quark operators. The theoretical framework is based on a combination of unitarized chiral perturbation theory and…
The chiral symmetry is applied to an extended constituent quark potential model. With random phase approximation (RPA), the model comprises sea quark excitations. To obtain the pseudoscalar $\pi$ meson as a Goldstone boson, the quark…
We study multi-particle state contributions to the QCD two-point functions of the axial-vector and pseudo-scalar quark bilinears in a finite spatial volume. For sufficiently small quark masses one expects three-meson states with two…
We investigate the creation of scalar particles inside a region delimited by a bubble which is expanding with non-zero acceleration. The bubble is modelled as a thin shell and plays the role of a moving boundary, thus influencing the…
Chiral-scale perturbation theory $\chi$PT$_\sigma$ has been proposed as an alternative to chiral $SU(3)_L\times SU(3)_R$ perturbation theory which explains the $\Delta I = 1/2$ rule for kaon decays. It is based on a low-energy expansion…
We study the two-dimensional two-component Coulomb gas in the canonical ensemble and at inverse temperature $\beta>2$. In this regime, the partition function diverges and the interaction needs to be cut off at a length scale $\lambda\in…
We report a project to study scalar particles by lattice QCD simulations. After a brief introduction of the current situation of lattice study of the sigma meson, we describe our numerical simulations of scalar mesons, $\sigma$ and…
Motivated by the possibility that nonets of scalar mesons might be described as mixtures of "two quark" and "four quark" components, we further study a toy model in which corresponding chiral nonets (containing also the pseudoscalar…
We illustrate how the two-pole structures of the $\Lambda(1405)$ emerge from the underlying universal chiral dynamics that describe the coupled-channel interactions between octet baryons and pseudo-Nambu-Goldstone bosons. Specifically, we…
We present preliminary results for the chiral behavior of charged pseudo-Goldstone-boson masses and decay constants. These are obtained in simulations with N_f=2+1 flavors of tree-level, O(a)-improved Wilson sea quarks. In these…
Non-linear sigma models with scalar fields taking values on $\mathbb{C}\mathbb{P}^n$ complex manifolds are addressed. In the simplest $n=1$ case, where the target manifold is the $\mathbb{S}^2$ sphere, we describe the scalar fields by means…