Related papers: Valence QCD: Connecting QCD to the Quark Model
Using a ladder-rainbow kernel previously established for the soft scale of light quark hadrons, we explore the extension to masses and electroweak decay constants of ground state pseudoscalar and vector quarkonia and heavy-light mesons in…
In earlier publications we have analyzed the strong and radiative decays of heavy hadrons in a formalism which incorporates both heavy-quark and chiral symmetries. In particular, we have derived a heavy-hadron chiral Lagrangian whose…
Numerical simulations of the quarkonium spin splittings are done in the framework of lattice nonrelativistic quantum chromodynamics (NRQCD). At leading order in the velocity expansion the spin splittings are of $O(M_Q v^4)$, where $M_Q$ is…
An overview of the theory and phenomenology of hadrons and QCD is provided from a Dyson-Schwinger equation viewpoint. Following a discussion of the definition and realisation of light-quark confinement, the nonperturbative nature of the…
Parton distribution functions (PDFs) are nonperturbative quantities describing the relation between a hadron and quarks and gluons within it. We propose to extract PDFs from QCD global analysis of "data" generated by lattice QCD…
The results of a recent quenched lattice QCD simulation for charmed baryons are presented. In contrast to a previous calculation, it is found that hyperfine splittings are in agreement with quark model expectations and comparable to…
Dynamical chiral-symmetry breaking in QCD is studied with the Schwinger-Dyson (SD) formalism based on lattice QCD data, i.e., LQCD-based SD formalism. We extract the SD kernel function $K(p^2)$ in an Ansatz-independent manner from the…
This is the first study on the double-gluon hybrid, which consists of one valence quark and one valence antiquark together with two valence gluons. We concentrate on the one with the exotic quantum number $J^{PC} = 2^{+-}$ that conventional…
There now exist several theoretical technologies for treating weak decays of heavy flavour hadrons that are genuinely based on QCD without having to invoke a deus ex machina. I focus on one of those, which employs an expansion in inverse…
As a simple model for dark matter, we propose a QCD-like theory based on $\rm{SU}(2)$ gauge theory with one flavor of dark quark. The model is confining at low energy and we use lattice simulations to investigate the properties of the…
Lattice QCD has generated a wealth of data in hadronic physics over the last two decades. Until relatively recently, most of this information has been within the "quenched approximation" where virtual quark--anti-quark pairs are neglected.…
Generalized parton distributions encompass a wealth of information concerning the three-dimensional quark and gluon structure of the nucleon, and thus provide an ideal focus for the study of hadron structure using lattice QCD. The special…
We show that maximally twisted mass fermions can be employed to regularize on the lattice the fully unquenched QCD+QED theory with vanishing $\theta$-term. We discuss how the critical mass of the up and down quarks can be conveniently…
The chiral Lagrangian describing the low-energy behavior of N_f=2+1+1 twisted mass lattice QCD is constructed through O(a^2). In contrast to existing results the effects of a heavy charm quark are consistently removed, leaving behind a…
The dressing of bare massless quarks is described with a spatial theory based on the self-consistent solution of the QCD field equations. After quantization these equations are expressed in terms of quark and gluon creation and annihilation…
We present preliminary lattice results for the nonperturbative tensor structure of the vector and axial-vector quark-antiquark vertices in QCD. Our lattice calculations are for $N_f=2$ mass-degenerate Wilson fermion flavors whose quark mass…
The chiral nonanalytic behaviour of quark-flavor contributions to the magnetic moments of octet baryons are determined in full, quenched and partially-quenched QCD, using an intuitive and efficient diagrammatic formulation of quenched and…
We use the variational principle of Quantum HadronDynamics, an alternative formulation of Quantum ChromoDynamics, to determine the wavefunction of valence quarks in a baryon at a low value of Q^2. This can be used to predict the structure…
Quantum Chromodynamics (QCD) is the theory governing the strong interaction of particles. It describes the interactions that bind quarks and gluons into protons and neutrons, and binds these into nuclei. We believe QCD to be as fundamental…
The Quark-Meson-Coupling model, which self-consistently relates the dynamics of the internal quark structure of a hadron to the relativistic mean fields arising in nuclear matter, provides a natural explanation to many open questions in low…