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arXiv · 2103.16991

Determination of the Collins-Soper Kernel from Lattice QCD

Maximilian Schlemmer·Alexey Vladimirov·Christian Zimmermann·Michael Engelhardt·Andreas Schäfer
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Abstract

We present lattice results for the non-perturbative Collins-Soper (CS) kernel, which describes the energy-dependence of transverse momentum-dependent parton distributions (TMDs). The CS kernel is extracted from the ratios of first Mellin moments of quasi-TMDs evaluated at different nucleon momenta.The analysis is done with dynamical $N_f=2+1$ clover fermions for the CLS ensemble H101 ($a=0.0854\,\mathrm{fm}$, $m_π=m_K=422\,\mathrm{MeV}$). The computed CS kernel is in good agreement with experimental extractions and previous lattice studies.

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Maximilian Schlemmer, Alexey Vladimirov, Christian Zimmermann, Michael Engelhardt, Andreas Schäfer. 2021-07-07. Determination of the Collins-Soper Kernel from Lattice QCD. https://doi.org/10.1007/jhep08(2021)004

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