Related papers: Light cone nucleon wave function in the quark-soli…
A detailed study of nucleon parton distribution functions is performed within a radiative Next-to-Next-to Leading Order (NNLO) parton model whose low-scale input is rigidly described by wave functions which include quarks and dressing…
A model example is given of how properties of the hadronic light-cone wave function are revealed in a particular high energy process. The meson wave function is derived in scalar quark QCD. We apply it to compute the form of the cross…
The electroweak properties of nucleons and hyperons are calculated in a relativistic constituent quark model. The baryons are treated as three quark bound states, and the diagrams of perturbation theory are considered on the light front.…
The electromagnetic form factors provide important insight into the internal structure of the nucleon and continue to be of major interest for experiment and phenomenology. For an intermediate range of momenta the form factors can be…
We calculate the electroweak properties of nucleons and hyperons in a relativistic constituent quark model using the light-front formalism. The parameters of the model, namely the constituent quark mass and the confinement scale, can be…
We study hadronic wave functions using an instanton model for the QCD vacuum. The wave functions are defined in terms of gauge invariant Bethe Salpeter amplitudes which we have determined numerically using a Monte Carlo simulation of the…
Quark light cone momentum distributions in the nucleon are calculated in a relativistic 3-body approach to the NJL model by using a simple 'static approximation' for the Faddeev kernel. A method is presented which automatically satisfies…
The spin structure of the nucleon is studied in a light-cone description of the nucleon where the Fock expansion is truncated to consider only valence quarks. Transverse momentum dependent parton distributions and transverse-spin densities,…
Through an impulse approximation analysis of single spin Sivers and Collins asymmetries in the Bjorken limit, the possibility to extract the quark transverse-momentum distributions in the neutron from semi-inclusive deep inelastic electron…
The structure of the 1/Nc expansion for the baryon distribution amplitude in QCD is tested using quark models. Earlier conjectures about this structure based on the evolution equation and on the soft-pion theorem are confirmed by the model…
Moments of light cone quark density, helicity, and transversity distributions are calculated in unquenched lattice QCD at $\beta = 5.5$ and $\beta = 5.3$ using Wilson fermions on $ 16^3 \times 32 $ lattices. These results are combined with…
We study the behaviour of lightcone wavefunctions, in coarse transverse lattice gauge theory, when one or more parton lightcone momenta are small. This probes the limit of hadron structure at large and small Bjorken x. Finite-energy…
The unpolarized, helicity and transversity parton distribution functions of the nucleon are studied within a convolution model where the bare nucleon is dressed by its virtual meson cloud. Using light-front time-ordered perturbation theory,…
We report on numerical lattice QCD calculations of some of the low moments of the nucleon structure functions. The calculations are carried out with gauge configurations generated by the RBC and UKQCD collaborations with (2+1)-flavors of…
The matrix elements of electroweak currents which occur in exclusive decays of heavy hadrons are evaluated in the nonperturbative light-cone Fock representration. In general, each semileptonic exclusive decay amplitude receives two…
We discuss a few, apparently different (but actually, tightly related) problems: 1. The relation between QCD and valence quark model, 2. The evaluation of the nonlocal condensate $ \la \bar{q}(x)q(0)\ra $, its relation to heavy-light…
Expectations for the momentum distribution of nonperturbative charm and bottom quarks in the proton are derived from a variety of models for the Fock space wave function on the light cone.
Using gauge invariant hadronic two- and three- density correlators we extract information on the spatial distributions of quarks in hadrons, and on hadron shape and multipole moments within quenched lattice QCD. Combined with the…
The widely used nonperturbative wave functions and distribution functions of QCD are determined as matrix elements of light-ray operators. These operators appear as large momentum limit of nonlocal hadron operators or as summed up local…
Background The intense current experimental interest in studying the structure of the deuteron and using it to enable accurate studies of neutron structure motivate us to examine the four-dimensional space-time nature of the nuclear wave…