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arXiv · hep-ex/9511013

Measurements of the Proton and Deuteron Spin Structure Function g2 and Asymmetry A2

The E143 Collaboration·K. Abe et al
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Abstract

We have measured proton and deuteron virtual photon-nucleon asymmetries A2p and A2d and structure functions g2p and g2d over the range 0.03<x<0.8 and 1.3<Q2<10 (GeV/c)2 by inelastically scattering polarized electrons off polarized ammonia targets. Results for A2 are significantly smaller than the positivity limit sqrt(R) for both targets. Within experimental precision, the g2 data are well-described by the twist-2 contribution g2WW. Twist-3 matrix elements have been extracted and are compared to theorectical predictions.

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The E143 Collaboration, K. Abe et al. 1995-11-30. Measurements of the Proton and Deuteron Spin Structure Function g2 and Asymmetry A2. https://doi.org/10.1103/physrevlett.76.587

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