Scale setting, sigma terms and the Feynman-Hellman theorem

Understand

The authors recently presented new values for the octet baryon sigma terms.

• These were extracted using the Feynman-Hellman theorem from a chiral perturbation theory fit to octet baryon mass data from the PACS-CS collaboration.
• Of particular interest is the precise determination of the strangeness sigma term $\sigma_s = 21 \pm 6$ MeV.
• In this work, we elaborate on the critical effect which the choice of scale setting has on this value.