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arXiv · 1710.06466

Finite continuum quasi distributions from lattice QCD

Christopher Monahan·Kostas Orginos
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Abstract

We present a new approach to extracting continuum quasi distributions from lattice QCD. Quasi distributions are defined by matrix elements of a Wilson-line operator extended in a spatial direction, evaluated between nucleon states at finite momentum. We propose smearing this extended operator with the gradient flow to render the corresponding matrix elements finite in the continuum limit. This procedure provides a nonperturbative method to remove the power-divergence associated with the Wilson line and the resulting matrix elements can be directly matched to light-front distributions via perturbation theory.

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Christopher Monahan, Kostas Orginos. 2017-10-17. Finite continuum quasi distributions from lattice QCD. https://doi.org/10.1051/epjconf%2F201817506004

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