6533b832fe1ef96bd129a587

RESEARCH PRODUCT

Polarized structure functions in a constituent quark scenario

Sergio ScopettaMarco TrainiVicente Vento

subject

QuarkPhysicsNuclear and High Energy PhysicsParticle physicsStructure functionHigh Energy Physics::PhenomenologyNuclear TheoryFOS: Physical sciencesConstituent quarkFísicaPartonPolarization (waves)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Low energyNeutronHigh Energy Physics::ExperimentNucleonNuclear Experiment

description

Using a simple picture of the constituent quark as a composite system of point-like partons, we construct the polarized parton distributions by a convolution between constituent quark momentum distributions and constituent quark structure functions. Using unpolarized data to fix the parameters we achieve good agreement with the polarization experiments for the proton, while not so for the neutron. By relaxing our assumptions for the sea distributions, we define new quark functions for the polarized case, which reproduce well the proton data and are in better agreement with the neutron data. When our results are compared with similar calculations using non-composite constituent quarks the accord with the experiments of the present scheme is impressive. We conclude that, also in the polarized case, DIS data are consistent with a low energy scenario dominated by composite constituents of the nucleon.

10.1016/s0370-2693(98)01218-0http://arxiv.org/abs/hep-ph/9804302