Experimental Evidence for Simple Relations between Unpolarized and Polarized Parton Distributions

الأصل · EN

The Pauli exclusion principle is advocated for constructing the proton and neutron deep inelastic structure functions in terms of Fermi-Dirac distributions that we parametrize with very few parameters. It allows a fair description of the recent NMC data on Fᵖ₂(x,Q²) and Fⁿ₂(x,Q²) at Q²=4 GeV², as well as the CCFR neutrino data at Q²=3 and 5 GeV². We also make some reasonable and simple assumptions to relate unpolarized and polarized quark parton distributions and we obtain, with no additional free parameters, the spin dependent structure functions xgᵖ₁(x,Q²) and xgⁿ₁(x,Q²). Using the correct Q² evolution, we have checked that they are in excellent agreement with the very recent SMC proton data at Q²=10 GeV² and the SLAC neutron data at Q²=2 GeV².