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QCD analysis of Lambda hyperon production in DIS target-fragmentation region

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 نشر من قبل Federico Alberto Ceccopieri
 تاريخ النشر 2012
  مجال البحث
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We consider Lambda-hyperon production in the target-fragmentation region of semi-inclusive deep-inelastic scattering within the framework of fracture functions. We present a first attempt to determine the flavour and energy dependences of these non-perturbative distributions through a simultaneous QCD-based fit to available neutral- and charged-current semi-inclusive-DIS cross sections. Predictions based on the resulting nucleon-to-Lambda fracture functions are in good agreement with data and observables not included in the regression. The successful prediction of the $Q^2$ dependence of the Lambda multiplicity notably represents the first validation of the perturbative framework implied by fracture functions.

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