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arXiv · hep-ph/9409455

Target Mass Effects in QCD Bjorken Sum Rule

Hiroyuki Kawamura·Tsuneo Uematsu
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Abstract

We investigate the target mass effects in QCD Bjorken sum rule. The magnitude of the target mass correction is estimated in a variety of methods employing positivity bound as well as the experimental data for the asymmetry parameters. It turns out that the target mass correction is sizable at low $Q^2$ of the order of a few GeV$^2$, where the QCD correction is significant. We show that there exists uncertainty due to target mass effects in determining the QCD effective coupling constant $α_s(Q^2)$ from the Bjorken sum rule.

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Hiroyuki Kawamura, Tsuneo Uematsu. 1994-09-30. Target Mass Effects in QCD Bjorken Sum Rule. https://doi.org/10.1016/0370-2693(94)01507-9

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