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DOE OSTI · 1049363

Spin Structure Functions from Electron Scattering

Choi, Seonho
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Abstract

The spin structure of the nucleon can play a key testing ground for Quantum Chromo-Dynamics (QCD) at wide kinematic ranges from smaller to large four momentum transfer Q{sup 2}. The pioneering experiments have confirmed several QCD sum rules at high Q{sup 2} where a perturbative picture holds. For a full understanding of QCD at various scales, various measurements were made at intermediate and small Q{sup 2} region and their interpretation would be a challenging task due to the non-perturbative nature. Jefferson Lab has been one of the major experimental facilities for the spin structure with its polarized electron beams and various polarized targets. A few QCD sum rules have been compared with the measured spin structure functions g{sub 1}(x, Q{sup 2}) and g{sub 2}(x, Q{sup 2}) at low Q{sup 2} and surprising results have been obtained for the spin polarizabilities, {gamma}{sub 0} and {delta}{sub LT} . As for the proton spin structure functions, the lack of data for g{sub 2}(x,Q{sup 2}) structure functions has been complemented with a new experiment at Jefferson Lab, SANE. The results from SANE will provide a better picture of the proton spin structure at a wide kinematic range in x and Q{sup 2}.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDSFOUR MOMENTUM TRANSFERNUCLEONSPOLARIZED TARGETSPROTONSQUANTUM CHROMODYNAMICSRANGESCATTERINGSPINSTRUCTURE FUNCTIONSSUM RULESTESTING

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Choi, Seonho. 2012-09-01. Spin Structure Functions from Electron Scattering. https://www.osti.gov/biblio/1049363

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