Related papers: Quantifying the nucleon's pion cloud with transver…
We study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of…
We investigate the transverse charge density in the longitudinally as well as transversely polarized deuteron using the recent empirical description of the deuteron electromagnetic form factors in the framework of holographic QCD. The…
We use Chiral Perturbation Theory to compute the nucleon mass-shift due to finite volume and temperature effects. Our results are valid up to next-to-leading order in the "\eps-regime" (mL ~ m\beta << 1) as well as in the "p-regime" (mL ~…
We present a consistent calculation of the structure functions within a light-front constituent quark model of the nucleon. Relativistic effects and the relevance of the covariance constraints are analyzed for polarized parton…
Virtual Compton scattering off nucleons and pions at low energies is discussed. Predictions for the generalized polarizabilities of the nucleon are presented within the framework of heavy-baryon chiral perturbation theory and the linear…
The specificities of transverse polarization with respect to helicity of ultrarelativistic fermions are pointed out. For massless fermions, a covariant transversity four-vector is defined, up to a kind of gauge transformation. The…
We propose to measure neutron and deuteron transversity TMDs. The quark transversity distributions of the nucleon are decoupled from the deuteron gluon transversity in the $Q^2$ evolution due to the chiral-odd property in the…
Experimental data on electromagnetic and weak form factors of the nucleon are analyzed in a two-component model with a quark-like intrinsic structure surrounded by a meson cloud. The contribution from strange quarks is discussed and…
We consider the spin-averaged nucleon forward Compton scattering amplitude in heavy baryon chiral perturbation theory including all terms to order ${\cal O} (q^4)$. The chiral prediction for the spin-averaged forward Compton scattering…
We analyze hyperon and nucleon mass shifts in nuclear matter using chiral perturbation theory. Expressions for the mass shifts that include strong interaction effects at leading order in the density are derived. Corrections to our results…
The baryon electromagnetic form factors are expressed in terms of two-dimensional densities describing the distribution of charge and magnetization in transverse space at fixed light-front time. We calculate the transverse densities of the…
The elastic and $\gamma \to \pi$ transition form factors of the pion along with its usual static observables are calculated within a light-front field approach to the constituent quark model. The focus of this exercise in a simple model is…
Partial restoration in nuclear matter of the chiral symmetry of QCD is discussed together with some of its possible signals. Estimates of corrections to the leading, linear dependence of the quark condensate are found to be small, implying…
Hard, or high transverse momentum, pion photoproduction can be a tool for probing the parton structure of the beam and target. We discuss the perturbative and soft processes that contribute, and show how regions where perturbative processes…
An explicitly crossing-symmetric decomposition of the pion-pion scattering amplitudes into low- and high-energy components is established. The high-energy components are entirely determined by absorptive parts at high energies. With the…
We extend the standard second order effective chiral Lagrangian of pions and nucleons by considering the coupling to an external gravitational field. As an application we calculate one-loop corrections to the one-nucleon matrix element of…
We calculate the differential cross section for semi-inclusive pion production in electron proton reactions using a model where the physical quark fluctuates with some probability to quark plus pion. The kinematic regions for a…
The next-to-leading order chiral pion-nucleon Lagrangian contains seven finite low-energy constants. Two can be fixed from the nucleon anomalous magnetic moments and another one from the quark mass contribution to the neutron-proton mass…
In this paper we study the gluon distribution functions in nucleons and pions at a low resolution $Q^2$ scale. This is an important issue since parton densities at low $Q^2$ have always been taken as an external input which is adjusted…
The electromagnetic form factors of the nucleon are calculated in an extended chiral constituent-quark model where the effective interaction is described by the exchange of pseudoscalar, vector, and scalar mesons. Two-body current-density…