Related papers: Are There Diquarks in the Nucleon?
Nucleon structure and the origin and nature of the nuclear force are investigated in the context of a QCD-based effective field theory and the path-integral method of hadronization. We start from a microscopic model of quarks and diquarks…
In this thesis a model framework for describing baryons as diquark-quark bound states is presented which is formulated in an explicitly covariant manner. The relativistic bound state problem for three quarks is considered. Diquarks are…
The absolute mass of neutrinos and their nature are presently unknown. Aggregate matter has a coherent weak charge leading to a repulsive interaction mediated by a neutrino pair. Near its range at micron distances the virtual neutrinos are…
The quark-gluon properties of the nucleon are probed by a host of recent and planned experiments. These involve elastic, deep-inelastic, semi-inclusive deep-inelastic (SIDIS), and deeply-virtual Compton scattering. A light-front description…
In Poincar\'e-covariant continuum treatments of the three valence-quark bound-state problem, the force behind dynamical chiral symmetry breaking also generates nonpointlike, interacting diquark correlations in the nucleon and its…
The baryon structure is investigated in a covariant diquark-quark model. In this approach baryons emerge as relativistic bound states of a constituent quark and a $0^{+}$ or $1^{+}$ diquark. After solving the Bethe-Salpeter Equation for the…
Neutrinos are among the most mysterious particles in nature. Their mass hierarchy and oscillations, as well as their antiparticle properties, are being intensively studied in experiments around the world. Moreover, in many models of physics…
We explain how the emergent phenomenon of dynamical chiral symmetry breaking ensures that Poincar\'e covariant analyses of the three valence-quark scattering problem in continuum quantum field theory yield a picture of the nucleon as a…
We analyze topological objects in pure QCD in the presence of external quarks by calculating the distributions of instanton and monopole densities around static color sources. We find a suppression of the densities close to external sources…
We discuss the structure of the nuclear force using a lagrangian derived from hadronization of a chiral quark and diquark model. A generalized trace log formula including meson and nucleon fields is expanded to the order in which relevant…
We introduce an improved mass formula for the nucleon and delta resonances and show how it emerges from AdS/QCD in a straightforward extension of the 'metric soft wall' gravity dual. The resulting spectrum depends on just one adjustable…
We investigate the electromagnetic form factors of nucleons within a simple relativistic quark spectator-diquark model using the light-cone formalism. Melosh rotations are applied to both quark and vector diquark. It is shown that the…
Several recent experiments have reported evidence for a narrow feature in the K(+)-neutron system, an apparent resonant state ~ 100 MeV above threshold and with a width < 25 MeV. This state has been labelled as Theta(+) (previously as…
The hadron-quark phase transition in the core of massive neutron stars is studied with a newly constructed two-phase model. For nuclear matter, a nonlinear Walecka type model with general nucleon-meson and meson-meson couplings, recently…
A review of recent nucleon structure calculations within lattice QCD is presented. The nucleon excited states, the axial charge, the isovector momentum fraction and helicity distribution are discussed, assessing the methods applied for…
The mass spectra of the excited heavy baryons consisting of two light (u,d,s) and one heavy (c,b) quarks are calculated in the heavy-quark--light-diquark approximation within the constituent quark model. The light quarks, forming the…
We give a review of the calculations of the masses of tetraquarks with two and four heavy quarks in the framework of the relativistic quark model based on the quasipotential approach and QCD. The diquark-antidiquark picture of heavy…
We apply a dynamical three-constituent quark light-front model to study the proton. The dynamics is based on the notion of a diquark (bound or virtual) as the dominant interaction channel, which paramaterizes a contact interaction between…
Accessing a full picture of the internal structure of hadrons would be a key topic of hadron physics, with the main motivation to study the strong interaction binding the visible matter. Furthermore, the underlying structure of known exotic…
We are discussing the properties of the QCD vacuum which might be important especially for the understanding of hadrons with small quark core size $\sim0.3\,fm.$ We assume that at these distances the QCD vacuum can be described by the…