The known classification of excited baryons based on the dynamical
symmetry group SU(6)x O(3) can be understood in the framework of the 1/N_c
expansion [1]. The application to masses [2-5] based on the experimentally
determined masses can now be extended to the case of baryon masses
obtained in lattice QCD [6,7]. The work to be presented analyses the ground
state as well as the excited multiplets [70,1^-],[56,0^+] and [56,2^+].
Mass relations which are valid up to corrections 1/N_c^2, or
$\frac{1}{N_c}(m_s-m_{u,d})$,or $(m_s-m_{u,d})^2$ are tested and
conclusions on quark mass dependence of the effective mass operators and
minimal sets of effective mass operators are obtained.
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[7] R.G. Edwards, N.Mathur, D.G. Richards, S.J. Wallace, Phys.Rev.D87, 054506 (2013).