Related papers: Quantifying the nucleon's pion cloud with transver…
Measurements of single-spin asymmetries for semi-inclusive electro-production of pions and kaons in deep-inelastic scattering with transverse target polarization open a new window on the transverse quark and gluon structure of the nucleon.…
We calculate the cross section of a pion diffraction dissociation in two jets with large transverse momenta originating from a hard gluon exchange between the pion constituents. To the leading logarithmic accuracy (in energy), the…
The anapole form factor of the nucleon is calculated in chiral perturbation theory in leading order. To this order, the form factor originates from the pion cloud, and is proportional to the non-derivative parity-violating pion-nucleon…
We perform a new Monte Carlo QCD analysis of pion parton distribution functions, including, for the first time, transverse momentum dependent pion-nucleus Drell-Yan cross sections together with $p_{\rm T}$-integrated Drell-Yan and leading…
We carry out a comparative analysis of the transversities and the longitudinally polarized parton distribution functions in light of the first empirical extraction of the transversity distributions recently done by Anselmino et al. It is…
The leading chiral contributions to the quark and gluon components of the proton spin are calculated using heavy-baryon chiral perturbation theory. Similar calculations are done for the moments of the generalized parton distributions…
In the framework of chiral effective field theory of delta resonances, nucleons and pions interacting with background gravitational field we calculate the gravitational form factors of the nucleon up to fourth order in the small scale…
The long-distance structure of the interacting nucleon receives important contributions from its couplings to light hadronic degrees of freedom -- a light meson cloud -- while an analogous nonperturbative mechanism is expected to generate…
The parton content of the nucleon is explored within a meson-cloud model developed to derive light-cone wave functions for the physical nucleon. The model is here applied to study electromagnetic form factors, distribution amplitudes and…
We consider chiral perturbation theory with an explicit broad $\sigma$-meson and study its contribution to the scalar form factors of the pion and the nucleon. Our goal is to learn more about resonance saturation in the scalar sector.
This talk will explain how ground state matrix elements specifying moments of quark density and spin distributions in the nucleon have been calculated in full QCD, show how physical extrapolation to the chiral limit including the physics of…
The nucleon axial charge is calculated as a function of the pion mass in full QCD. Using domain wall valence quarks and improved staggered sea quarks, we present the first calculation with pion masses as light as 354 MeV and volumes as…
With a special intention of clarifying the underlying spin contents of the nucleon, we investigate the generalized form factors of the nucleon, which are defined as the $n$-th $x$-moments of the generalized parton distribution functions,…
Transverse spin and transverse momentum distribution functions of the constituents of the nucleon are a crucial input for a complete description of the nucleon. COMPASS measured such for longitudinally and transversely polarized deuterons…
The electromagnetic and gravitational form factors of the nucleon are studied simultaneously using a covariant quark-diquark approach, and the pion cloud effect on the form factors is explicitly discussed. In this study, the electromagnetic…
It is widely known that the nucleon scalar charge is proportional to the pion-nucleon sigma term as one of the important low energy observables of QCD. Especially interesting to us is the physics of the nucleon scalar charge densities. This…
We compute the light-cone momentum distributions of pions in the nucleon in chiral effective theory using both pseudovector and pseudoscalar pion-nucleon couplings. For the pseudovector coupling we identify \delta-function contributions…
A two-dimensional Fourier transform of hadron form factors allows to determine their charge density in transverse space. We show that this method can be applied to any virtual photon induced transition, such as \gamma *(q)+N -> \pi N. Only…
We investigate the nucleon tensor charge from current experiments by a combined analysis of the Collins asymmetries in two hadron production in $e^+e^-$ annihilations and semi-inclusive hadron production in deep inelastic scattering…
We have developed a field theory formalism to calculate $in$-$medium$ properties of hadrons within a unified approach that exploits a single Lagrangian to describe simultaneously both matter background and meson fluctuations. In this paper…