Determination of αs and the nucleon spin decomposition using recent polarized structure function data

John Ellis, Marek Karliner

Research output: Contribution to journalArticlepeer-review

Abstract

New data on polarized μ-p and e-p scattering permit a first determination of αs using the Bjorken sum rule, as well as higher precision in determining the nucleon spin decomposition. Using perturbative QCD calculations to {A figure is presented} for the non-singlet combination of structure functions, we find αs(2.5 GeV2) = 0.375-0.081+0.062, corresponding to αs(MZ2) = 0.122-0.009+0.005, and using calculations to {A figure is presented} for the singlet combination we find Δu = 0.83 ± 0.03, Δd = -0.43 ± 0.03, Δs = -0.10±0.03, ΔΣ Δu + Δd + Δs = 0.31 ± 0.07, at a renormalization scale Q2 = 10 GeV2. Perturbative QCD corrections play an essential role in reconciling the interpretations of data taken using different targets. We discuss systematic uncertainties in the above numbers, which are dominated by higher-twist effects and lead, we estimate, to αs(MZ2) = 0.118-0.014+0.007. The Δq determinations are used to update predictions for the couplings of massive Cold Dark Matter particles and axions to nucleons.

Original languageEnglish
Pages (from-to)397-406
Number of pages10
JournalPhysics Letters B
Volume341
Issue number3-4
DOIs
StatePublished - 5 Jan 1995

Fingerprint

Dive into the research topics of 'Determination of αs and the nucleon spin decomposition using recent polarized structure function data'. Together they form a unique fingerprint.

Cite this