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arXiv · 2412.13138

Nucleon sigma terms with a variational analysis from Lattice QCD

Lorenzo Barca·Gunnar Bali·Sara Collins
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Abstract

We determine the nucleon-sigma terms from lattice QCD. We find that the dominant excited state contamination in the nucleon three-point function with a scalar current is due to the transition between the nucleon and a S-wave scattering state of a nucleon and a scalar (sigma) meson. In this proof-of-concept study, we analyse a single $N_f=3$ ensemble with the unphysically large pion mass $M_\pi=429$ MeV. Excited state contamination is substantially reduced compared to the standard method when employing nucleon-sigma type interpolating operators within a generalised eigenvector analysis.

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Lorenzo Barca, Gunnar Bali, Sara Collins. 2024-12-17. Nucleon sigma terms with a variational analysis from Lattice QCD. https://arxiv.org/abs/2412.13138

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