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arXiv · hep-ph/0205108

Quadrupole Moments of N and Delta in the 1/N_c Expansion

Alfons J. Buchmann·Janice A. Hester·Richard F. Lebed
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Abstract

We calculate expressions for the quadrupole moments of nonstrange baryons in which the number of QCD color charges is N_c. Using only the assumption of single-photon exchange, we obtain 4 relations among the 6 moments, and show how all of them may be obtained from Q_{Δ^+ p} up to O(1/N_c^2) corrections. We compare to the N_c=3 case, and obtain relations between the neutron charge radius and quadrupole moments. We also discuss prospects for the measurement of these moments.

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Alfons J. Buchmann, Janice A. Hester, Richard F. Lebed. 2002-05-27. Quadrupole Moments of N and Delta in the 1/N_c Expansion. https://doi.org/10.1103/physrevd.66.056002

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