Related papers: Sivers Function in the MIT Bag Model
We calculate the non-zero Boer-Mulders functions of sea quarks inside the proton in a meson-baryon fluctuation model. The results show that the transverse spin effects of sea quarks in an unpolarized nucleon are sizable. Using the obtained…
We investigate the Wigner distributions of $\bar{u}$ and $\bar{d}$ quarks in a proton using the overlap representation within the light cone formalism. Using the light cone wave functions which are obtained from the baryon-meson fluctuation…
The transverse momentum dependent helicity distributions of valence quarks are calculated in the light-cone diquark model by adopting two different approaches. We use the model results to analyze the $P_{h\perp}$-dependent double spin…
The class of interference fragmentation functions, arising from interference among different hadron production channels, is reconsidered. Their symmetry properties with respect to chiral transformations allow building spin asymmetries where…
We consider the recent RHIC data on the transverse single spin asymmetry (SSA) A_N, measured in p(transv. polarized) p -> pi^0 X processes at mid-rapidity by the PHENIX collaboration. The measurement is consistent with a vanishing SSA. We…
The transversity parton distribution remains a poorly known cornerstone in the nucleon spin structure. While the Collins effect in spin asymmetries in Semi-Inclusive DIS (SIDIS) is one crucial tool to address the transversity function, the…
We consider the Sivers, Collins and transversity functions as extracted from SIDIS and e+e- experimental data and investigate to what extent they might explain the large Single Spin Asymmetries (SSA) observed in proton-proton inclusive…
We present a model for dihadron fragmentation functions, describing the fragmentation of a quark into two unpolarized hadrons. We tune the parameters of our model to the output of the PYTHIA event generator for two-hadron semi-inclusive…
The extraction of transverse momentum dependent distributions (TMDs) in semi-inclusive deep inelastic scattering (SIDIS) is complicated by the presence of both initial- and final-state nonperturbative physics. We recently proposed measuring…
We discuss in detail the option to access the transversity distribution function $h_1(x)$ by utilizing the analyzing power of interference fragmentation functions in two-pion production inside the same current jet. The transverse…
We discuss our present understanding of the transverse spin structure of the nucleon and of related properties originating from parton transverse motion. Starting from the transversity distribution and the ways to access it, we then address…
The cross section for semi-inclusive deep inelastic scattering can be decomposed in terms of 18 structure functions. At low transverse momentum of the detected hadron, the structure functions can be expressed in terms of…
Previously we showed that, based only on C and SU(2) invariance, the difference cross sections of hadrons with opposite charge in SIDIS e+N\to l+h+X is expressed solely in terms of the valence-quark densities and certain non-singlet…
The single-transverse spin asymmetry(SSA) for hadron production in the transversely polarized proton scattering receives major contribution from Sivers effect, which can be systematically described within the collinear twist-3 factorization…
We discuss the recent interpretation of quark-distribution functions in the plane transverse to the light-cone direction. Such a mapping is model independent and allows one to build up multidimensional pictures of the hadron and to develop…
The non-valence spin-flavor structure of the nucleon extracted from semi-inclusive measurements of polarized deep inelastic scattering depends strongly on the transverse momentum of the detected hadrons which are used to determine the…
We discuss the recent interpretation of quark distribution functions in the plane transverse to the light-cone direction. Such a mapping is model independent and allows one to build multidimensional pictures of the hadron and to develop a…
The Collins effect describes the modulation of the hadron production by a transversely polarized quark with the sine of the polar angle, $\varphi$, between the produced hadron's transverse momentum and the quark spin. We employ a quark-jet…
We advocate the existence of a new type of $k_\perp$-dependent functions. In contrast to the well-known Boer-Mulders function, the presented new functions can be associated with the collective alignment of quark spin vectors. Moreover, the…
In this paper we briefly review the transverse momentum dependent generalized parton model and its application to the study of azimuthal asymmetries in the distribution of leading hadrons (mainly pions) inside large transverse momentum jets…