97 research outputs found
Nonperturbative Quark Sea Asymmetries
The effects of nonperturbatively generated ``quark sea'' have been
investigated to determine the flavor structure of the octet baryons. The chiral
constituent quark model (CQM), which is known to provide a satisfactory
explanation of the proton spin and related issues in the nonperturbative
regime, is able to explain the qualitative generation of the requisite amount
of quark sea. The importance of quark sea has been studied at different values
of the Bjorken scaling variable by including it phenomenologically in the
sea quark distribution functions. The results for the quark sea asymmetries
like , and Gottfried integral for
the octet baryons strengthen the significance of quark sea at lower values of
.Comment: 9 pages. Presented at the Gribov-80 Memorial Workshop on Quantum
Chromodynamics and Beyond held at ICTP, Trieste in May 2010. (To appear in
the World Scientific Proceedings
Single Transverse Spin Asymmetries in Semi-inclusive Deep Inelastic Scattering in a Spin-1 Diquark Model
The observed results for the azimuthal single spin asymmetries (SSAs) of the
proton, measured in the semi-inclusive deep inelastic scattering (SIDIS), can
be explained by the final-state interaction (FSI) from the gluon exchange
between the outgoing quark and the target spectator system. SSAs require a
phase difference between two amplitudes coupling the target with opposite spins
to the same final state. We have used the model of light front wave functions
(LFWFs) consisting of a spin- system as a composite of a
spin- fermion and a spin-1 vector boson to estimate the SSAs. The
implications of such a model have been investigated in detail by considering
different coupling constants. The FSIs also produce a complex phase which can
be included in the LFWFs to calculate the Sivers and Boer-Mulders distribution
functions of the nucleon.Comment: 23 pages, 4 figures. To appear in Eur. Phys. J.
- …