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arXiv · hep-ph/0601177

Virtual meson cloud of the nucleon and generalized parton distributions

B. Pasquini·S. Boffi
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Abstract

We present the general formalism required to derive generalized parton distributions within a convolution model where the bare nucleon is dressed by its virtual meson cloud. In the one-meson approximation the Fock states of the physical nucleon are expanded in a series involving a bare nucleon and two-particle, meson-baryon, states. The baryon is assumed here to be either a nucleon or a $Δ$ described within the constituent quark model in terms of three valence quarks; correspondingly, the meson, assumed to be a pion, is described as a quark-antiquark pair. Explicit expressions for the unpolarized generalized parton distributions are obtained and evaluated in different kinematics.

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B. Pasquini, S. Boffi. 2006-03-15. Virtual meson cloud of the nucleon and generalized parton distributions. https://doi.org/10.1103/physrevd.73.094001

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