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arXiv · 0709.0714

The permutation group S_N and large Nc excited baryons

Dan Pirjol·Carlos Schat
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Abstract

We study the excited baryon states for an arbitrary number of colors Nc from the perspective of the permutation group S_N of N objects. Classifying the transformation properties of states and quark-quark interaction operators under S_N allows a general analysis of the spin-flavor structure of the mass operator of these states, in terms of a few unknown constants parameterizing the unknown spatial structure. We explain how to perform the matching calculation of a general two-body quark-quark interaction onto the operators of the 1/Nc expansion. The inclusion of core and excited quark operators is shown to be necessary. Considering the case of the negative parity L=1 states transforming in the MS of S_N, we discuss the matching of the one-gluon and the Goldstone-boson exchange interactions.

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Dan Pirjol, Carlos Schat. 2008-06-25. The permutation group S_N and large Nc excited baryons. https://doi.org/10.1103/physrevd.78.034026

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