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  • Open Access

Next-to-Leading-Order Corrections and Factorization for Transverse Single-Spin Asymmetries

Daniel Rein*, Marc Schlegel†, Patrick Tollkühn‡, and Werner Vogelsang§

  • *Contact author: da.rein@student.uni-tuebingen.de
  • †Contact author: marc.schlegel@uni-tuebingen.de
  • ‡Contact author: patrick.tollkuehn@uni-tuebingen.de
  • §Contact author: werner.vogelsang@uni-tuebingen.de
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Phys. Rev. Lett. 135, 251901 – Published 16 December, 2025

DOI: https://doi.org/10.1103/fhxq-njl2

Abstract

We present next-to-leading-order QCD corrections for the cross sections for ℓp↑→hX and ℓp↑→jetX with transversely polarized initial protons. These cross sections are known to be power-suppressed in QCD and probe twist-3 parton correlation functions in the proton. Our calculation exhibits the full complexity of a perturbative QCD analysis beyond leading power, involving in particular various derivatives of the parton correlation functions. We demonstrate that collinear factorization for these single-spin observables holds at one loop. We also present exploratory phenomenological results for the NLO single-spin asymmetry in ep↑→hX and compare to data from the HERMES experiment.

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Physics Subject Headings (PhySH)

See Also

Transverse nucleon single-spin asymmetry for single-inclusive hadron and jet production at NLO accuracy

Daniel Rein, Marc Schlegel, Patrick Tollkühn, and Werner Vogelsang
Phys. Rev. D 112, 114024 (2025)

Article Text

Supplemental Material

References (45)

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Outline

Information

Phys. Rev. Lett. 135, 251901– Published 16 December, 2025
  • Received 31 March 2025
  • Revised 12 September 2025
  • Accepted 7 November 2025
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