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The electroproduction of the $Δ$(1232) in the chiral quark-soliton model

A. Silva·D. Urbano·T. Watabe·M. Fiolhais·K. Goeke
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Abstract

We calculate the ratios E2/M1 and C2/M1 for the electroproduction of the $Δ$(1232) in the region of photon virtuality $0<-q^2<1$ GeV$^2$. The magnetic dipole amplitude M1 is also presented. The theory used is the chiral quark-soliton model, which is based in the instanton vaccum of the QCD. The calculations are performed in flavor SU(2) and SU(3) taking rotational ($1/N_c$) corrections into account. The results for the ratios agree qualitatively with the available data, although the magnitude of both ratios seems to underestimate the latest experimental results.

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A. Silva, D. Urbano, T. Watabe, M. Fiolhais, K. Goeke. 2000-04-17. The electroproduction of the $Δ$(1232) in the chiral quark-soliton model. https://doi.org/10.1016/s0375-9474(00)00195-0

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