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DOE OSTI · 1614987

Renormalization and matching for the Collins-Soper kernel from lattice QCD

Ebert, Markus A.·Stewart, Iain W.·Zhao, Yong
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Abstract

The Collins-Soper kernel, which governs the energy evolution of transverse- momentum dependent parton distribution functions (TMDPDFs), is required to accurately predict Drell-Yan like processes at small transverse momentum, and is a key ingredient for extracting TMDPDFs from experiment. Earlier we proposed a method to calculate this kernel from ratios of the so-called quasi-TMDPDFs determined with lattice QCD, which are defined as hadronic matrix elements of staple-shaped Euclidean Wilson line operators. Here we provide the one-loop renormalization of these operators in a regularization-independent momentum subtraction (RI'/MOM) scheme, as well as the conversion factor from the RI'/MOM-renormalized quasi-TMDPDF to the \( \overline{\mathrm{MS}} \) scheme. We also propose a procedure for calculating the Collins-Soper kernel directly from position space correlators, which simplifies the lattice determination.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSDrell-Yan processEuclideanQCD phenomenologyWilson loopcorrelation functiondistribution functionlatticelattice field theory simulationpartonquantum chromodynamicsrenormalizationtransverse momentumtransverse momentum dependence

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Ebert, Markus A., Stewart, Iain W., Zhao, Yong. 2020-03-17. Renormalization and matching for the Collins-Soper kernel from lattice QCD. https://doi.org/10.1007/jhep03(2020)099

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