Predictions for the proton lifetime in minimal nonsupersymmetric SO(10) models: An update

We present our best estimates of the uncertainties due to heavy particle threshold corrections on the unification scale ${\mathit{M}}_{\mathit{U}}$, intermediate scale ${\mathit{M}}_{\mathit{I}}$, and coupling constant ${\mathrm{\alpha }}_{\mathit{U}}$ in the minimal nonsupersymmetric SO(10) models. Using recent data from the CERN ${\mathit{e}}^{+}$ ${\mathit{e}}^{\mathrm{-}}$ collider LEP on ${\sin }^2$ ${\mathrm{\theta }}_{\mathit{W}}$ and ${\mathrm{\alpha }}_{\mathrm{strong}}$ to obtain the two-loop-level predictions for ${\mathit{M}}_{\mathit{U}}$ and ${\mathrm{\alpha }}_{\mathit{U}}$, we update the predictions for the proton lifetime in minimal nonsupersymmetric SO(10) models.