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arXiv · 1704.05457

The spin-dependent quark beam function at NNLO

Radja Boughezal·Frank Petriello·Ulrich Schubert·Hongxi Xing
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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 $N$-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.

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Radja Boughezal, Frank Petriello, Ulrich Schubert, Hongxi Xing. 2017-04-18. The spin-dependent quark beam function at NNLO. https://doi.org/10.1103/physrevd.96.034001

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