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arXiv · 1009.2481

Soft-Gluon Resummation and the Valence Parton Distribution Function of the Pion

Matthias Aicher·Andreas Schäfer·Werner Vogelsang
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Abstract

We determine the valence parton distribution function of the pion by performing a new analysis of data for the Drell-Yan process $π^- N\to μ^+μ^-X$. Compared to previous analyses, we include next-to-leading-logarithmic threshold resummation effects in the calculation of the Drell-Yan cross section. As a result of these, we find a considerably softer valence distribution at high momentum fractions $x$ than obtained in previous next-to-leading order analyses, in line with expectations based on perturbative-QCD counting rules or Dyson-Schwinger equations.

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Matthias Aicher, Andreas Schäfer, Werner Vogelsang. 2010-12-10. Soft-Gluon Resummation and the Valence Parton Distribution Function of the Pion. https://doi.org/10.1103/physrevlett.105.252003

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