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arXiv · hep-ph/0207092

Delta --> N gamma in Large-Nc QCD

E. Jenkins·X. Ji·A. V. Manohar
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Abstract

The decay Delta^+ --> p gamma is studied in the 1/N_c expansion of QCD. The ratio of the helicity amplitudes is determined to be A_{3/2}/A_{1/2} = \sqrt{3} + O(1/N_c^2). Equivalently, the ratio E2/M1 of the multipole amplitudes is predicted to be order 1/N_c^2.

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E. Jenkins, X. Ji, A. V. Manohar. 2002-07-05. Delta --> N gamma in Large-Nc QCD. https://doi.org/10.1103/physrevlett.89.242001

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