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arXiv · 1311.1578

Phenomenology of nonperturbative charm in the nucleon

Abstract

We perform a comprehensive analysis of the role of nonperturbative (or intrinsic) charm in the nucleon, generated through Fock state expansions of the nucleon wave function involving five-quark virtual states represented by charmed mesons and baryons. We consider contributions from a variety of charmed meson-baryon states and find surprisingly dominant effects from the (Dbar^{*0} Lambda_c+) configuration. Particular attention is paid to the existence and persistence of high-x structure for intrinsic charm, and the x dependence of the c-cbar asymmetry predicted in meson-baryon models. We discuss how studies of charmed baryons and mesons in hadronic reactions can be used to constrain models, and outline future measurements that could further illuminate the intrinsic charm component of the nucleon.

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T. J. Hobbs, J. T. Londergan, W. Melnitchouk. 2013-11-07. Phenomenology of nonperturbative charm in the nucleon. https://doi.org/10.1103/physrevd.89.074008

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