English

The spin-dependent quark beam function at NNLO

High Energy Physics - Phenomenology 2017-08-09 v2 Nuclear Theory

Abstract

We calculate the beam function for longitudinally-polarized quarks through next-to-next-to-leading order (NNLO) in QCD perturbation theory. This is the last missing ingredient needed to apply the factorization theorem for the NN-jettiness event-shape variable in polarized collisions through the NNLO level. We present all technical details of our derivation. As a by-product of our calculation we provide the first independent check of the previously-obtained unpolarized quark beam function. We anticipate that our result will have phenomenological applications in describing data from polarized collisions.

Keywords

Cite

@article{arxiv.1704.05457,
  title  = {The spin-dependent quark beam function at NNLO},
  author = {Radja Boughezal and Frank Petriello and Ulrich Schubert and Hongxi Xing},
  journal= {arXiv preprint arXiv:1704.05457},
  year   = {2017}
}

Comments

18 pages, 3 figures, references added, corrections made in some equations

R2 v1 2026-06-22T19:20:26.917Z