Polarized Parton Distribution, Orbital Angular Momentum, and the Violation of a{sub 8}
- Physics Department, Tafresh University, Tafresh (Iran, Islamic Republic of)
- Institute for Studies in Physics and Mathematics, IPM, Tehran (Iran, Islamic Republic of)
We use the so-called valon model, to describe the spin structure of the nucleon. We show that about 40% of the nucleon spin is carried by the polarized valence quarks. The remaining part comes from the gluon polarization and the orbital angular momentum. It is shown that the sea quark contributions to the spin of any hadron is simply marginal and consistent with zero. We also found that the value of a{sub 8} is substantially smaller than the value inferred from hyperon--{beta} decay, suggesting that full SU(3) symmetric assumption needs to be reconsidered. New and emerging experimental data tend to support this finding. Finally, we show that within the model presented here the experimental data on the polarized structure functions g{sub 1}{sup p,n,d} are reproduced.
- OSTI ID:
- 21293431
- Journal Information:
- AIP Conference Proceedings, Vol. 1105, Issue 1; Conference: DIFFRACTION 2008: International workshop on diffraction in high energy physics, La Londe-les-Maures (France), 9-14 Sep 2008; Other Information: DOI: 10.1063/1.3122168; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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