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arXiv · 0710.4423

Transverse momentum distributions of quarks from the lattice using extended gauge links

Bernhard U. Musch·Philipp Hägler·Andreas Schäfer·Meinulf Göckeler·Dru B. Renner·John W. Negele·LHPC Collaboration
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Abstract

We present preliminary numerical studies in Lattice QCD related to the intrinsic transverse momentum distribution of partons in the nucleon. We employ non-local operators, consisting of spatially separated quark creation and annihilation operators connected by a straight Wilson line. A clear signal is already obtained from a small number of configurations at a pion mass of about 600 MeV. As an example, we demonstrate that we can obtain the first x-moment of the transverse momentum dependent parton distribution function f_1^{n=1}(k_T) from our data. Our results, which are not renormalized, show a Gaussian-like distribution. The root mean squared transverse momentum is about 560 MeV for a Gaussian fit, close to phenomenological values.

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Bernhard U. Musch, Philipp Hägler, Andreas Schäfer, Meinulf Göckeler, Dru B. Renner, John W. Negele, LHPC Collaboration. 2007-10-24. Transverse momentum distributions of quarks from the lattice using extended gauge links. https://arxiv.org/abs/0710.4423

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