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arXiv · 0803.4119

Determination of the effective strong coupling constant alpha_{s,g_1}(Q^2) from CLAS spin structure function data

A. Deur·V. Burkert·J. P. Chen·W. Korsch
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Abstract

We present a new extraction of the effective strong coupling constant α_{s,g_1}(Q^2). The result agrees with a previous determination and extends the measurement of the low and high Q^2 behavior of α_{s,g_1}(Q^2) that was previously deduced from sum rules. In particular, it experimentally verifies the lack of Q^2-dependence of α_{s,g_1}(Q^2) in the low Q^2 limit. This fact is necessary for application of the AdS/CFT correspondence to QCD calculations. We provide a parameterization of α_{s,g_1}(Q^2) thatcan equivalently be used to parameterize the Q^2-dependence of the generalized Gerasimov-Drell-Hearn and Bjorken sums.

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A. Deur, V. Burkert, J. P. Chen, W. Korsch. 2008-07-21. Determination of the effective strong coupling constant alpha_{s,g_1}(Q^2) from CLAS spin structure function data. https://doi.org/10.1016/j.physletb.2008.06.049

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