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Parton distributions from the lattice

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 نشر من قبل Wolfram Schroers
 تاريخ النشر 2005
  مجال البحث
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 تأليف Wolfram Schroers




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I review the current status of lattice calculations for two selected observables related to nucleon structure: the second moment of the unpolarized parton distribution, <x> (u-d), and the first moment of the polarized parton distribution, the non-singlet axial coupling gA. The major challenge is the requirement to extract them sufficiently close to the chiral limit. In the former case, there still remains a puzzling disagreement between lattice data and experiment. For the latter quantity, however, we may be close to obtaining its value from the lattice in the immediate future.



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