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Experimental determination of the evolution of the Bjorken integral at low Q^2

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 نشر من قبل Alexandre Deur
 تاريخ النشر 2004
  مجال البحث
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We extract the Bjorken integral Gamma^{p-n}_1 in the range 0.17 < Q^2 < 1.10 GeV^2 from inclusive scattering of polarized electrons by polarized protons, deuterons and 3He, for the region in which the integral is dominated by nucleon resonances. These data bridge the domains of the hadronic and partonic descriptions of the nucleon. In combination with earlier measurements at higher Q^2, we extract the non-singlet twist-4 matrix element f_2.

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