The fit uses the ${{\mathit \Xi}^{0}}$, ${{\mathit \Xi}^{-}}$, and ${{\overline{\mathit \Xi}}^{+}}$ masses and the ${{\mathit \Xi}^{-}}−{{\mathit \Xi}^{0}}$ mass difference. It assumes that the ${{\mathit \Xi}^{-}}$ and ${{\overline{\mathit \Xi}}^{+}}$ masses are the same.