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arXiv · 2207.07630

Zero-jettiness beam functions at N$^3$LO

Arnd Behring
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Abstract

The zero-jettiness beam functions describe collinear emissions from initial state legs and appear in the factorisation theorem for cross sections in the limit of small zero-jettiness. They are an important building block for slicing schemes for colour-singlet production at hadron colliders. We report on our ongoing calculation of this quantity at next-to-next-to-next-to-leading order (N$^3$LO) in QCD, highlighting in particular the aspects of partial fraction relations and the calculation of master integrals.

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Arnd Behring. 2022-07-15. Zero-jettiness beam functions at N$^3$LO. https://arxiv.org/abs/2207.07630

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