Related papers: Nucleon Spin Distributions From Recent SMC, SLAC a…
The quark helicity measured in polarized deep inelastic scattering is different from the quark spin in the rest frame of the nucleon. We point out that the quark spin distributions $\Delta q_{RF}(x)$ are connected with the quark helicity…
We investigate the sea quark polarization in the nucleon by means of a combined next to leading order analysis to the recently enlarged set of inclusive and semi-inclusive polarized deep inelastic scattering data. Using the Lagrange…
We summarize recent attempts to calculate the flavor asymmetry of the nucleon's sea quark distributions in the large-$N_c$ limit, where the nucleon can be described as a soliton of an effective chiral theory. We discuss the leading-twist…
We propose new method which allows determination of the strange-sea quark spin distribution in the nucleon through measurement of various inclusive and semi-inclusive polarized deep inelastic electron- or muon-proton reactions. It is shown,…
The quark and gluon structure of the proton has been under intense experimental and theoretical investigation for five decades. Even for the distributions of the well-studied valence quarks, challenges such as the value of the down quark to…
The recent high precision SMC data on polarized $\mu p$ scatterings have again confirmed that very little of the proton spin is carried by quarks. To unravel the mystery of the proton spin structure, it is quite important to know the…
We investigate the possibility to measure the spin content carried by the different quark flavors in a nucleon by means of polarized deep inelastic scattering with $W^\pm$ exchange at HERA. Such measurements require a polarized proton beam.…
The flavor structure of the nucleon sea provides unique information to test the statistical parton distributions approach, which imposes strong relations between quark and antiquarks. These properties for unpolarized and helicity…
We have made next to leading order QCD fit to the deep inelastic spin asymmetries on nucleons and we have determined polarised quark and gluon densities. The functional form for such distributions was inspired by the unpolarised ones given…
Spin asymmetries of semi-inclusive cross sections for the production of positively and negatively charged hadrons have been measured in deep-inelastic scattering of polarized positrons on polarized hydrogen and 3He targets, in the kinematic…
The possibilities to determine the flavor structure of the polarized sea (antiquark) distributions of the nucleon via vector boson $(\gamma^*, W^{\pm}, Z^0)$ production at high energy polarized hadron--hadron colliders, such as the…
I review some recent developments in the study of quark flavor distributions in the nucleon, including (i) valence quark distributions and the quark-hadron duality prediction for the x -> 1 d/u ratio (ii) sea quark asymmetries and…
By assuming that there is no significant intrinsic polarization of the gluon, we have computed the polarized quark contributions to the proton's spin under SU(3) flavor symmetry breaking for the polarized sea and have performed a global…
Double-spin asymmetries of semi-inclusive cross sections for the production of identified pions and kaons have been measured in deep-inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions…
The strange sea quarks distributions of nucleons obtained by two global analyses based on available structure function data of muon and neutrino deep inelastic scatterings are different from the strange sea quark distribution measured by…
I deduce an inequality between the helicity and the transversity distribution of a quark in a nucleon, at small energy scales. Then I establish, thanks to the positivity constraint, a rigorous bound on longitudinally polarized valence quark…
The recent measurements of lepton nucleon scattering with polarised neutron and deuteron targets are analysed together with the previous polarised proton data in a mutually consistent way. The detailed $x$-dependence of the polarisation…
We review the current status and future prospects on the subject of flavor structure of the nucleon sea. The flavor structure of the nucleon sea provides unique information on the non-perturbative aspects of strong interactions allowing…
Analysis was performed of semi-inclusive and inclusive spin asymmetries determined from the polarized deep inelastic scattering by the Spin Muon Collaboration. Combined analysis of data for polarized deuterium and hydrogen targets allows…
We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range $0.003<x<0.7$ and $Q^2>$1 GeV$^2$.…