Measurements of the $Q^2$-Dependence of the Proton and Neutron Spin Structure Functions g1p and g1n

The E155 Collaboration; P. L. Anthony

doi:10.1016/s0370-2693(00)01014-5

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arXiv · hep-ph/0007248

Measurements of the $Q^2$-Dependence of the Proton and Neutron Spin Structure Functions g1p and g1n

The E155 Collaboration·P. L. Anthony

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Abstract

The structure functions g1p and g1n have been measured over the range 0.014 < x < 0.9 and 1 < Q2 < 40 GeV2 using deep-inelastic scattering of 48 GeV longitudinally polarized electrons from polarized protons and deuterons. We find that the Q2 dependence of g1p (g1n) at fixed x is very similar to that of the spin-averaged structure function F1p (F1n). From a NLO QCD fit to all available data we find $Γ_1^p - Γ_1^n =0.176 \pm 0.003 \pm 0.007$ at Q2=5 GeV2, in agreement with the Bjorken sum rule prediction of 0.182 \pm 0.005.

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The E155 Collaboration, P. L. Anthony. 2000-07-22. Measurements of the $Q^2$-Dependence of the Proton and Neutron Spin Structure Functions g1p and g1n. https://doi.org/10.1016/s0370-2693(00)01014-5

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