Ghil-Seok Yang, Hyun-Chul Kim
Considering simultaneously isospin and SU(3) flavor symmetry breakings, we investigate the complete mass splittings of SU(3) baryons within a chiral soliton model, a {}"model-independent approach" being employed. In linear order several new mass relations are derived, which are mostly generalizations of existing mass formulae. The dynamical quantities appearing in the expressions for the masses are fixed by fitting them to the masses of the baryon octet and the masses of $\Omega^{-}$ and $\Theta^{+}$ as input rather than by extracting them from a calculated self-consistent soliton profile. In particular, the consideration of isospin symmetry breaking allows us to use the experimental data of the whole octet baryon masses as input. We predict the masses of the baryon decuplet and antidecuplet without any further adjustable free parameter. In addition, we also obtain the pion-nucleon sigma term which turns out to be $\Sigma_{\pi N} = 36.4\pm3.9\,\mathrm{MeV}$. We get the ratio of the current light quark masses $R = 58.1\pm1.3$. The present results indicate that the recent experimental data for the $\Theta^{+}(1524)$ are compatible with the experimental data of the octet and decuplet masses.
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http://arxiv.org/abs/1010.3792
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