Related papers: Handedness inside the proton
I present some results about transverse momentum dependent distribution and fragmentation functions. Firstly I illustrate a simple model, with predictive power about the energy behavior, for T-odd, chiral odd functions. Moreover I propose a…
The special role played by singly polarized high-energy hadron-hadron collisions in Spin Physics is discussed: In such processes, the measured and the calculated quantities can be and have been directly compared with each other --- without…
The imbalance of dijets produced in hadronic collisions has been used to extract the average transverse momentum of partons inside the hadrons. In this paper we discuss new contributions to the dijet imbalance that could complicate or even…
We discuss a possible explanation of the 25 year old mystery of the large transverse spin asymmetries found in many semi-inclusive hadron-hadron reactions. We obtain the first reliable information about the transverse polarized quark…
Improved measurements of the proton's structure are now possible thanks to significant technical advances that allow us to probe the proton with polarized photons. These measurements have shown that the proton is not as simple as previously…
A surprisingly large transverse polarization of $\Lambda$ hyperons in unpolarized hadron-nucleon/nucleus collisions has been observed for 50 years, and the origin of this polarization remains an important open question. Recently,…
The experimental observations that led to the quark structure of matter and the development of hadron physics are reviewed with emphasis on the discoveries of mesons and baryons, starting in the 1940s with the pion and kaon which mediate…
Advances in experiment, theory and phenomenology of hadron spectroscopy are discussed. We focus on specific developments in the meson sector.
A brief review on the recent theoretical progress in hot/dense QCD is given. Special emphasis is put on the non-perturbative aspects of QCD plasma and the modification of hadron proporties near the critical temperature of chiral transition.
I give a brief overview of our current understanding of the internal partonic 3D structure of nucleons in momentum space. I discuss some recent extractions of transverse-momentum-dependent distributions for quarks, whose analyses in the…
We analyze the coherence properties of polarized neutrons, after they have interacted with a magnetic field or a phase shifter undergoing different kinds of statistical fluctuations. We endeavor to probe the degree of disorder of the…
By analyzing experimental data on semi-inclusive deep inelastic scattering off longitudinally polarized targets, we extract the transverse momentum dependence of the quark helicity distribution, i.e., the difference between the…
The electric polarizability of mesons, in particular, that of the charged pion, is studied in the framework of a semirelativistic description of hadrons as bound states of valence quarks in terms of a Hamiltonian composed of the…
Recent observations of exotic hadrons have stimulated the theoretical investigation of the internal structure of hadrons. While all hadrons are ultimately composed of quarks and gluons bound by the strong interaction, quark clustering…
A phenomenological description of single transverse spin effects in hadron-hadron inclusive processes is proposed, assuming a generalized factorization scheme and pQCD hard interactions. The transverse momentum, k_T, of the quarks inside…
Hadronization, the process by which energetic quarks evolve into hadrons, has been studied phenomenologically for decades. However, little experimental insight has been gained into the space-time features of this fundamentally…
The matter density distribution inside a hadron is evaluated using gauge-invariant correlation functions within the quenched and the unquenched theory. Comparison with the charge density distribution suggests that hadron deformation is a…
We analyse the role of partonic transverse motion in unpolarized Semi-Inclusive Deep Inelastic Scattering (SIDIS) processes. Imposing appropriate kinematical conditions, we find some constraints which fix an upper limit to the range of…
The study of two spin asymmetries in hadron-hadron collisions probes the details of fundamental particle interactions in ways infeasible to machines with unpolarized collisions. Within reach is how the proton spin is distributed among its…
We propose an inequality between the longitudinally polarized density and the transversity of a quark in a nucleon. This inequality, whose validity is limited to very small scales, is based on considerations about Lorentz transformations…