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

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 نشر من قبل Bernhard Ulrich Musch
 تاريخ النشر 2007
  مجال البحث
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 تأليف Bernhard U. Musch




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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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