Related papers: Quark model: recent issues
Systematic approaches to building up gauge invariant descriptions of charged fields, such as electrons or quarks, are described. Physically relevant descriptions must then be singled out from a multiplicity of possibilities and to this end…
We propose a phenomenological light-front wave function for hadrons with arbitrary twist-dimension (mesons, baryons and multiquark states), which gives the correct scaling behavior of structure functions (parton distributions) and form…
We perform a coupled-channels study of the $bb\bar c\bar c$ and $bc\bar b\bar c$ tetraquark systems in a molecular approach using a constituent quark model which has been widely used to satisfactorily describe a broad range of properties of…
There are many outstanding discrepancies comparing the predictions of perturbative QCD and measurements of the rate of production and decay of heavy quark systems. The problems include the $J/\psi \to \rho \pi$ puzzle, leading charmed…
Many new results on open and hidden charm spectroscopy have been obtained recently. We present a short review of the experimental findings in the meson sector, of the theoretical interpretations and of the open problems, with a discussion…
I introduce an entirely new dynamical description for exotic charmoniumlike hadrons, based upon the competing effects of the strong attraction between quarks in a diquark, and the inability of the diquark to hadronize on its own due to…
A good agreement between a flux tube-based quark model of light baryons (strange and nonstrange) and the $1/N_c$ expansion mass formula has been found in previous studies. In the present work a larger connection is established between the…
Rather than regarding the restriction of current lattice QCD simulations to quark masses that are 5--10 times larger than those observed, we note that this presents a wonderful opportunity to deepen our understanding of QCD. Just as it has…
In this paper we study the influence of hadronic resonances on the phase diagram calculated with an effective chiral flavour SU(3) model. We show that varying the couplings of the baryonic resonances to the attractive scalar and the…
The bound state of constituent quarks forming a $Qqq$ composite baryon is investigated in a QCD-inspired effective light-front model. The light-front Faddeev equations are derived and solved numerically. The masses of the spin 1/2 low-lying…
Hadron spectra and other properties of quark systems are studied in the framework of a non-relativistic spin-independent phenomenological model. The chosen confining potential is harmonic, which allowed us to obtain analytical solutions for…
In this work we study the properties of hadronic molecules in the heavy-quark sector. These have become increasingly important since from the beginning of this century a large number of states have been measured that for different reasons…
After a prologue which clarifies some issues left open in my last paper, the main features of the tetron model of elementary particles are discussed in the light of recent developments, in particular the formation of strong and electroweak…
A simple quark-diquark model for the baryons is constructed as a partial solution to the well known missing resonances problem. A complete classification of the baryonic states in the quark-diquark framework is given and the spectrum is…
The use of relativistic quark models with simple parametric wave functions for the understanding of the electromagnetic structure of nucleons together with their electromagnetic transition to resonances is discussed. The implications of…
The first results of a new application of the Thomas-Fermi statistical quark model to mesonic matter is presented. Interesting aspects of the theory are discussed, distinguishing such states from baryonic matter. A major motivation of this…
The momentum distributions of the constituent quarks inside the nucleon and the prominent electroproduced nucleon resonances are investigated in the two most sophisticated, available quark potential models, based respectively on the…
A recently proposed modified perturbation expansion for QCD is employed to evaluate the quark self-energies. Results of the order of 1/3 of the nucleon mass are obtained for the effective masses of the up and down quarks in a first…
A brief review on some recent progresses in our understanding of multi-quark components in baryons is presented. The multi-quark components in baryons seem to be mainly in colored quark cluster configurations rather than in ``meson cloud''…
We present a study of the baryon spectra for all flavor sectors within a constituent quark model. We address some of the outstanding problems in baryon spectroscopy, as for example the spin splitting evolution for te different flavor…