Speaker
Description
A lot of progress has been made in the direct determination of nucleon sigma terms. Using similar methods we consider the sigma terms of the other octet baryons as well. These are determined on CLS gauge field ensembles employing the Lüscher-Weisz gluon action and the Sheikholeslami-Wohlert fermion action with $N_\mathrm{f} = 2 + 1$. The ensembles analysed here have pion masses ranging from ${410}\,\mathrm{MeV}$ down to ${216}\,\mathrm{MeV}$ and lattice spacings covering a range between ${0.039}\,\mathrm{fm}$ and ${0.098}\,\mathrm{fm}$.
To tackle the well-known problem of excited state contamination we have studied the effect of different multi-state fits on the sigma terms. In order to investigate the systematic error arising from the varied treatment of the excited states we carry out the full analysis for different choices of multi-state fits. In the end, the sigma terms of the baryon octet are simultaneously extrapolated to the physical point taking the quark mass dependence and lattice spacing effects into account.
| Topical area | Structure of Hadrons and Nuclei |
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