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arXiv · 1605.08408

First Forcer results on deep-inelastic scattering and related quantities

B. Ruijl·T. Ueda·J. A. M. Vermaseren·J. Davies·A. Vogt
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Abstract

We present results on the fourth-order splitting functions and coefficient functions obtained using Forcer, a four-loop generalization of the Mincer program for the parametric reduction of self-energy integrals. We have computed the respective lowest three even-N and odd-N moments for the non-singlet splitting functions and the non-singlet coefficient functions in electromagnetic and nu+nu(bar) charged-current deep-inelastic scattering, and the N=2 and N=4 results for the corresponding flavour-singlet quantities. Enough moments have been obtained for an LLL-based determination of the analytic N-dependence of the nf^3 and nf^2 parts, respectively, of the singlet and non-singlet splitting functions. The large-N limit of the latter provides the complete nf^2 contributions to the four-loop cusp anomalous dimension. Our results also provide additional evidence of a non-vanishing contribution of quartic group invariants to the cusp anomalous dimension.

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B. Ruijl, T. Ueda, J. A. M. Vermaseren, J. Davies, A. Vogt. 2016-05-26. First Forcer results on deep-inelastic scattering and related quantities. https://arxiv.org/abs/1605.08408

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