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arXiv · hep-ex/9701004

Measurement of the Proton and Deuteron Spin Structure Function g_1 in the Resonance Region

The E143 Collaboration
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Abstract

We have measured the proton and deuteron spin structure functions g_1^p and g_1^d in the region of the nucleon resonances for W^2 < 5 GeV^2 and $Q^2\simeq 0.5$ and $Q^2\simeq 1.2$ GeV^2 by inelastically scattering 9.7 GeV polarized electrons off polarized $^{15}NH_3$ and $^{15}ND_3$ targets. We observe significant structure in g_1^p in the resonance region. We have used the present results, together with the deep-inelastic data at higher W^2, to extract $Γ(Q^2)\equiv\int_0^1 g_1(x,Q^2) dx$. This is the first information on the low-Q^2 evolution of Gamma toward the Gerasimov-Drell-Hearn limit at Q^2 = 0.

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The E143 Collaboration. 1997-01-09. Measurement of the Proton and Deuteron Spin Structure Function g_1 in the Resonance Region. https://doi.org/10.1103/physrevlett.78.815

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