Related papers: Spectrum of excited states using the stochastic La…
We study the $C=1$, $S=-2$, $I=0$ sector, where five excited $\Omega_c$ states have been recently observed by the LHCb Collaboration. We start from a recently developed unitarized baryon-meson model that takes, as bare baryon-meson…
We present results of our numerical calculation of the mass spectrum for isospin one-half and spin one-half non-strange baryons, i.e. the ground and excited states of the nucleon, in quenched lattice QCD. We use a new lattice discretization…
We present results on the QCD equation of state, obtained with two different improved dynamical staggered fermion actions and almost physical quark masses. Lattice cut-off effects are discussed in detail as results for three different…
Quark models taking into account the dynamical effects of hadronic decay often produce very different predictions for mass shifts in the hadron spectrum. The consequences for meson spectroscopy can be dramatic and completely obscure the…
We study mass spectra of a meson-meson system involving two light and two heavy quarks on an anisotropic lattice. The heavy quarks are treated in the static approximation. The dependence of the spectrum on the relative distance of the heavy…
We employ a variational basis with a number of $\bar{q}q$ and $\pi\pi$ lattice interpolating fields with quantum numbers of the $\rho$ resonance to extract the discrete energy spectrum in a finite volume. In the elastic region, this…
Recent findings on the spectrum of heavy-quark mesons from computer simulations of quarks and gluons in lattice QCD are summarized, with particular attention to quark-antiquark states bound by an excited gluon field. The validity of a…
This is a follow-up to our earlier work for the energies and the charge (vector) and matter (scalar) distributions for S-wave states in a heavy-light meson, where the heavy quark is static and the light quark has a mass about that of the…
We investigate the baryon mass spectrum in quenched lattice QCD with exact chiral symmetry. For 100 gauge configurations generated with Wilson gauge action at $ \beta = 6.1 $ on the $ 20^3 \times 40 $ lattice, we compute (point-to-point)…
Despite decades of research, we still lack a detailed quantitative understanding of the way quantum chromodynamics (QCD) generates the spectrum of hadrons. Precise experimental studies of the hadron excitation spectrum and the dynamics of…
We present an extension of the Hamiltonian of the two dimensional limit of the vibron model encompassing all possible interactions up to four-body operators. We apply this Hamiltonian to the modeling of the experimental bending spectrum of…
A simulation of quenched QCD with the overlap Dirac operator has been completed using 100 Wilson gauge configurations at beta = 6 on an 18^3 x 64 lattice and at beta = 5.85 on a 14^3 x 48 lattice, both in Landau gauge. We present results…
We study quantum oscillator lattice systems with disorder, in arbitrary dimension, requiring only partial localization of the associated effective one-particle Hamiltonian. This leads to a many-body localized regime of excited states with…
We have extended our program of QCD simulations with an improved Kogut-Susskind quark action to a smaller lattice spacing, approximately 0.09 fm. Also, the simulations with a approximately 0.12 fm have been extended to smaller quark masses.…
The ability to reliably measure the energy of an excited hadron in Lattice QCD simulations hinges on the accurate determination of all lower-lying energies in the same symmetry channel. These include not only single-particle energies, but…
Numerical simulations with access to all possible meson quantum numbers, J^{PC}, are presented using two-flavor (up and down) quenched twisted mass lattice QCD with three different lattice spacings and four different quark masses. The…
Recent lattice QCD results for the low-lying odd-parity excitations of the nucleon near the $N^{*}(1535)$ and $N^{*}(1650)$ resonance positions have revealed that the lattice QCD states have magnetic moments consistent with predictions from…
A system of two static quarks, at fixed distances r, and two light quarks is studied on an anisotropic lattice. Excitations by operators emphasizing quark or gluon degrees of freedom are examined. The maximum entropy method is applied in…
We develop and test a spectral-density analysis method, based on the introduction of smeared energy kernels, to extract physical information from two-point correlation functions computed numerically in lattice field theory. We apply it to a…
We present a study of lattice-QCD methods to determine the relevant hadronic form factors for radiative leptonic decays of pseudoscalar mesons. We provide numerical results for $D_s^+ \to \ell^+ \nu \gamma$. Our calculation is performed…