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arXiv · 1412.1296

Extracting meson-baryon contributions to the electroexcitation of the $N(1675){\frac{5}{2}}^-$ nucleon resonance

I. G. Aznauryan·V. D. Burkert
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Abstract

We report on the determination of the electrocouplings for the transition from the proton to the $N(1675){\frac{5}{2}}^-$ resonance state using recent differential cross section data on $e p \rightarrow eπ^+ n$ by the CLAS collaboration at $1.8 \le Q^2 < 4.5$GeV$^2$. The data have been analyzed using two different approaches, the unitary isobar model and fixed-t dispersion relations. The extracted $γ^* p\rightarrow N(1675){\frac{5}{2}}^-$ helicity amplitudes show considerable coupling through the $A^p_{1/2}$ amplitude, that is significantly larger than predicted three-quark contribution to this amplitude. The amplitude $A^p_{3/2}$ is much smaller. Both results are consistent with the predicted sizes of the meson-baryon contributions at $Q^2 \geq 1.8 $GeV$^2$ from the dynamical coupled-channel model.

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I. G. Aznauryan, V. D. Burkert. 2015-07-10. Extracting meson-baryon contributions to the electroexcitation of the $N(1675){\frac{5}{2}}^-$ nucleon resonance. https://doi.org/10.1103/physrevc.92.015203

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