We compute the self energies of the baryon octet and decuplet states at the one-loop level applying the manifestly covariant chiral Lagrangian. It is demonstrated that expressions consistent with the expectation of power counting rules arise if the self energies are decomposed according to the Passarino-Veltman scheme supplemented by a minimal subtraction. This defines a partial summation of the chiral expansion. A finite renormalization required to install chiral power counting rules leads to the presence of an infrared renormalization scale. Good convergence properties for the chiral loop expansion of the baryon octet and decuplet masses are obtained for natural values of the infrared scale. A prediction for the strange-quark matrix element of the nucleon is made.Comment: 36 pages, 4 figures, 8 tables. The revised manuscript contains a proof that given any one-loop integral that arises when computing one-baryon processes it is sufficient to renormalize the scalar master-loop functions of the Passarino-Veltman reduction in a manner that the latter are compatible with the expectation of chiral counting rule

We perform a chiral extrapolation of the baryon octet and decuplet masses in a relativistic formulation of chiral perturbation theory. A partial summation is assumed as implied by the use of physical baryon and meson masses in the one-loop diagrams. Upon a chiral expansion, our results are consistent with strict chiral perturbation theory at the next-to-next-to-next-to-leading order.All counter terms are correlated by a large-N c operator analysis. Our results are confronted with recent results of unquenched three-flavor lattice simulations. We adjust the parameter set to the pion-mass dependence of the nucleon and omega masses as computed by the BMW Collaboration and predict the pion-mass dependence of the remaining baryon octet and decuplet states. The current lattice simulations can be described accurately and smoothly up to pion masses of about 600 MeV. In particular, we recover the recent results of HSC without any further adjustments.

We compute the strangeness content of the baryon octet and decuplet states based on an analysis of recent lattice simulations of the BMW, PACS-CS, LHPC and HSC groups for the pion-mass dependence of the baryon masses. Our results rely on the relativistic chiral Lagrangian and large-N c sum rule estimates of the counter terms relevant for the baryon masses at N 3 LO. A partial summation is implied by the use of physical baryon and meson masses in the one-loop contributions to the baryon self energies. A simultaneous description of the lattice results of the BMW, LHPC, PACS-CS and HSC groups is achieved. From a global fit we determine the axial coupling constants F 0.45 and D 0.80 in agreement with their values extracted from semi-leptonic decays of the baryons. Moreover, various flavor symmetric limits of baron octet and decuplet masses as obtained by the QCDSF-UKQCD group are recovered. We predict the pion-and strangeness sigma terms and the pionmass dependence of the octet and decuplet ground states at different strange quark masses.

The chiral SU (3) Lagrangian with the baryon octet and decuplet fields is considered. The Q 2 counterterms involving the decuplet fields are constructed. We derive the correlation of the chiral parameters implied by the 1/N c expansion at leading order in QCD.

In our recent analysis of lattice data of the BMW, LHPC and PACS-CS groups we determined a parameter set of the chiral Lagrangian that allows a simultaneous description of the baryon octet and decuplet masses as measured by those lattice groups. The results on the baryon spectrum of the HSC group were recovered accurately without their inclusion into our six parameter fit. We show that the same parameter set provides an accurate reproduction of the recent results of the QCDSF-UKQCD group probing the baryon masses at quite different quark masses. This shows a remarkable consistency amongst the different lattice simulations. With even more accurate lattice data in the near future it will become feasible to determine all low-energy parameters relevant at N 3 LO.

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 Ξ mass predicted by the MILC collaboration is recovered in terms of a discontinuous chiral extrapolation.

The chiral SUð3Þ Lagrangian with pseudoscalar and vector D mesons and with the octet and decuplet baryons is considered. The leading two-body counter terms involving two baryon fields and two D meson fields are constructed in the open-charm sector. There are 26 terms. A combined expansion in the inverse of the charm quark mass and in the inverse of the number of colors provides sum rules that reduce the number of free parameters down to 5 only. Our result shows the feasibility of a systematic computation of the open-charm baryon spectrum based on coupled-channel dynamics.

In this talk we discuss at hand of two examples the crucial role played by self consistency in hadron physics. The first example concerns the quark-mass dependence of the baryon octet and decuplet masses. It is shown that within a self consistent one-loop approach based on the chiral Lagrangian the 'mysterious' quark-mass dependence of the Ξ mass predicted by the MILC collaboration may be recovered in terms of a discontinuous chiral extrapolation. 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. In the second example we discuss recent studies on the properties of D mesons in cold nuclear matter as they are predicted by coupled-channel dynamics. Here a self consistent many-body approach reveals the close interlink of the properties of D meson and open-charm baryon resonances in nuclear matter. The relevance of exotic baryon resonances for the spectral distortion of the D ± s in nuclear matter is pointed out.