Exclusive ρ0 electroproduction on the proton at CLAS
Document Type
Article
Publication Date
2009
Abstract
The ep → e ′ pρ0 reaction has been measured using the 5.754GeV electron beam of Jefferson Lab and the CLAS detector. This represents the largest ever set of data for this reaction in the valence region. Integrated and differential cross-sections are presented. The W , Q2 and t dependences of the cross-section are compared to theoretical calculations based on the t -channel meson-exchange Regge theory, on the one hand, and on quark handbag diagrams related to Generalized Parton Distributions (GPDs) on the other hand. The Regge approach can describe at the ≈ 30% level most of the features of the present data while the two GPD calculations that are presented in this article which succesfully reproduce the high-energy data strongly underestimate the present data. The question is then raised whether this discrepancy originates from an incomplete or inexact way of modelling the GPDs or the associated hard scattering amplitude or whether the GPD formalism is simply inapplicable in this region due to higher-twists contributions, incalculable at present.
Publication Title
The European Physical Journal A
Repository Citation
Morrow, S. A.; Biselli, Angela; and CLAS Collaboration, "Exclusive ρ0 electroproduction on the proton at CLAS" (2009). Physics Faculty Publications. 124.
https://digitalcommons.fairfield.edu/physics-facultypubs/124
Published Citation
S. A. Morrow et al. [CLAS Collaboration], "Exclusive ρ0 electroproduction on the proton at CLAS", The European Physical Journal A 39.5 (2009) p5-31.
DOI
10.1140/epja/i2008-10683-5
Peer Reviewed
Comments
Copyright 2009 EDP Science with Springer
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