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arXiv · hep-ph/0210278

Electromagnetic Properties of the Delta in the Large N and Chiral Limits

Thomas D. COhen
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Abstract

Relations between nucleon, $Δ$ and nucleon-$Δ$ electromagnetic properties associated with chiral physics which have been derived in a pure large-$N_c$ limit are greatly modified in a combined large $N_c$ and chiral limits; the large $N_c$ relations are valid for $(M_Δ-M_N)/m_π<<1$. The E2/M1 ratio for the nucleon-$Δ$ transition is shown to scale as $ε^{-1}$ (with $ε\sim 1/N_c$, $ε\sim m_π/Λ$ with $Λ$ a typical hadronic scale) in the combined large $N_c$ and chiral expansions as opposed to $N_c^{-2}$ in the pure large $N_c$ expansion.

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Thomas D. COhen. 2002-10-21. Electromagnetic Properties of the Delta in the Large N and Chiral Limits. https://doi.org/10.1016/s0370-2693(02)03274-4

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