P - PH - 9 50 22 27 Baryon Mass Splittings in the 1 / N c Expansion
نویسنده
چکیده
The I = 0; 1; 2; 3 mass splittings of the spin-1=2 octet and spin-3=2 decuplet baryons are analyzed in the 1=Nc expansion combined with perturbative avor breaking. We show there is considerable experimental evidence that the baryon masses satisfy the hierarchy predicted by this expansion. Since avor symmetry-breaking suppression factors alone are not su cient to describe the observed hierarchy, we conclude that there is rm evidence for the 1=Nc expansion in the baryon masses. Our analysis di ers from non-relativistic SU(6).
منابع مشابه
Baryon Hyperfine Mass Splittings in Large N QCD
The hyperfine mass splittings of baryons in largeN QCD are proved to be proportional to J. Hyperfine mass splittings are first allowed at order 1/N in the 1/N expansion. UCSD/PTH 93-19 hep-ph/9307244 July 1993
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