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arXiv · 0808.2564

Pionic transparency in semi-exclusive electroproduction off nuclei

Murat M. Kaskulov·Kai Gallmeister·Ulrich Mosel
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Abstract

We investigate the early onset of pionic color transparency ($π$CT) observed at Jefferson Laboratory (JLAB) in semi--exclusive pion electroproduction reaction $A(e,e'π^+)$ off nuclei. In the present description the primary $γ^*p \to π^+ n$ interaction is described very well both for the longitudinal and the transverse polarizations. For the final state interactions a coupled--channel treatment of the interactions of transmitted hadrons allows to go beyond the Glauber approximation. We show that a proper distinction between the soft hadronic and hard partonic components of the electroproduction amplitude is essential for a quantitative description of the measured nuclear transparency. The data are well reproduced if one assumes that point--like configurations are produced in the regime of hard deep--inelastic scattering (DIS) off partons and dominate the transverse channel.

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Murat M. Kaskulov, Kai Gallmeister, Ulrich Mosel. 2009-02-02. Pionic transparency in semi-exclusive electroproduction off nuclei. https://doi.org/10.1103/physrevc.79.015207

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