Related papers: Estimates of the Nucleon Tensor Charge
We present results on the nucleon scalar, axial and tensor charges as well as on the momentum fraction, and the helicity and transversity moments. The pion momentum fraction is also presented. The computation of these key observables is…
The electromagnetic and axial form factors of the nucleon are evaluated in twisted mass QCD with two degenerate flavors of light, dynamical quarks. The axial charge g_A, magnetic moment and the Dirac and Pauli radii are determined for pion…
The data from the last seven experiments performed on polarized deep--inelastic scattering on proton and neutron (or deuteron) targets have been analyzed in search of a precise determination of the spin fraction carried by the quarks in the…
We review the information on the spin and orbital angular momentum structure of the nucleon encoded in the T-even transverse momentum dependent parton distributions within light-cone quark models. Model results for azimuthal spin…
We study the charge distributions of the valence quarks inside nucleon in the transverse coordinate space, which is conjugate to the transverse momentum space. We compare the results with the charge distributions in the impact parameter…
We recall the definitions and the basic properties of the transversity distributions $h^{q,\bar q}_1(x,Q^2)$ and the corresponding nucleon tensor charges $\delta q(Q^2)$. We briefly comment on different estimates from several…
To obtain further information on the geometric shape of the nucleon, the proton charge form factor is decomposed into two terms, which are connected respectively with a spherically symmetric and an intrinsic quadrupole part of the proton's…
We present a calculation of the Mellin moments of the nucleon transverse quark spin densities extracted from the unpolarized and transversity generalized form factors. We use three $N_F=2+1+1$ ensembles of twisted mass fermions with quark…
If physics beyond the Standard Model enters well above the electroweak scale, its low-energy effects are described by Standard Model Effective Field Theory. Already at dimension six many operators involve the antisymmetric quark tensor…
We investigated the transverse charge densities in the nucleon in nuclear matter within the framework of the in-medium modified Skyrme model. The medium modification of the nucleon electromagnetic form factors are first discussed. The…
We considered the electro- and photoproduction of \rho and other vector mesons with moderately large transverse momentum in the scattering of unpolarized electrons on unpolarized nucleons and nuclei. For these processes we have analyzed how…
Using the expansion of the baryon wave function in a series of products of single quark bispinors (Dirac orbitals), the nonsinglet axial and tensor charges of a nucleon are calculated. The leading term yields $g_A = 1.27$ in good agreement…
We give a brief overview of recent progress in lattice QCD simulations that is enabling precision studies of the three-dimensional structure of the nucleon. We present results on nucleon charges and second Mellin moments of parton…
The axial charges of the nucleon and the well-established N* resonances are studied within a consistent framework. For the first time the axial charges of the N* resonances are produced for the relativistic constituent quark model. The…
We investigate the charge distributions for the $u$ and $d$ quarks in transverse coordinate space in a light-front quark-diquark model for the nucleons using the overlaps of the wave functions constructed from the soft-wall AdS/QCD…
I calculate the quark contributions to the axial and tensor charges and the spin structure of the proton. The result indicates that the valence current quark spins carry 1/3 of the proton spin, the total contribution of quark spins to the…
Longitudinal and transverse quark momentum distributions in the nucleon are calculated from a phenomenological quark-nucleon vertex function obtained through an investigation of the nucleon electromagnetic form factors within a light-front…
Electromagnetic form factors obtained from the overlap of light front wave functions (LFWFs) have been used to study the transverse densities of charge and magnetization. The calculations have been carried out to develop a relation between…
The nucleon spin-averaged forward virtual Compton tensor determines important physical quantities such as electromagnetically-induced mass differences of nucleons, and two-photon exchange contributions in hydrogen spectroscopy. It depends…
Two-nucleon momentum distributions are calculated for the ground states of nuclei with mass number $A\leq 8$, using variational Monte Carlo wave functions derived from a realistic Hamiltonian with two- and three-nucleon potentials. The…