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On the possibility of a discontinuous quark-mass dependence of baryon octet and decuplet masses

A. Semke·M. F. M. Lutz
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Abstract

We compute the quark-mass dependence of the baryon octet and decuplet masses within the $χ$-MS scheme at the one-loop level. The results are confronted with recent lattice QCD simulations of the MILC collaboration. A fair reproduction of the quark-mass dependence as suggested by the lattice simulations is obtained up to pion masses of about 700 MeV. Based on the chiral one-loop results we predict that the dependence of the baryon octet and decuplet masses on the quark-masses is discontinuous. Typically the pion-mass dependence is smooth up to about 300 MeV only. This is a consequence of self consistency imposed on the partial summation, i.e. the masses used in the loop functions are identical to those obtained from the baryon self energies. The 'mysterious' quark-mass dependence of the Xi mass predicted by the MILC collaboration is recovered in terms of a discontinuous chiral extrapolation.

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A. Semke, M. F. M. Lutz. 2011-12-28. On the possibility of a discontinuous quark-mass dependence of baryon octet and decuplet masses. https://doi.org/10.1016/j.nuclphysa.2007.02.011

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