${{\boldsymbol N}}$ BARYONS($\boldsymbol S$ = 0, $\boldsymbol I$ = 1/2) ${{\mathit p}}$, ${{\mathit N}^{+}}$ = ${\mathit {\mathit u}}$ ${\mathit {\mathit u}}$ ${\mathit {\mathit d}}$; ${{\mathit n}}$, ${{\mathit N}^{0}}$ = ${\mathit {\mathit u}}$ ${\mathit {\mathit d}}$ ${\mathit {\mathit d}}$ INSPIRE search

# ${{\boldsymbol p}}$ $I(J^P)$ = $1/2(1/2^{+})$

 ${{\mathit p}}$ MASS (atomic mass units u) $1.00727646662 \pm0.00000000009$ u (S = 3.1)
 ${{\mathit p}}$ MASS (MeV) $938.272081 \pm0.000006$ MeV
 $\vert {\mathit m}_{{{\mathit p}}}−{\mathit m}_{{{\overline{\mathit p}}}}\vert /{\mathit m}_{{{\mathit p}}}$ $<7 \times 10^{-10}$   CL=90.0%
 ${{\overline{\mathit p}}}/{{\mathit p}}$ CHARGE-TO-MASS RATIO, $\vert {\mathit q_{{{\overline{\mathit p}}}}\over {\mathit m}_{{{\overline{\mathit p}}}}}\vert /({\mathit q_{{{\mathit p}}}\over {\mathit m}_{{{\mathit p}}}}$) $1.00000000000 \pm0.00000000007$
 ($\vert {\mathit q_{{{\overline{\mathit p}}}}\over {\mathit m}_{{{\overline{\mathit p}}}}}\vert -{\mathit q_{p}\over {\mathit m}_{{{\mathit p}}}})/{\mathit q_{{{\mathit p}}}\over {\mathit m}_{{{\mathit p}}}}$ $(0.1 \pm6.9) \times 10^{-11}$
 $\vert \mathit q_{{{\mathit p}}}~+~\mathit q_{{{\overline{\mathit p}}}}\vert /{{\mathit e}}$ $<7 \times 10^{-10}$   CL=90.0%
 $\vert {{\mathit q}_{{p}}}+{{\mathit q}_{{e}}}\vert /{{\mathit e}}$ $<1 \times 10^{-21}$
 ${{\mathit p}}$ MAGNETIC MOMENT $2.7928473446 \pm0.0000000008$ $\mu _{\mathit N}$
 ${{\overline{\mathit p}}}$ MAGNETIC MOMENT $-2.792847344 \pm0.000000004$ $\mu _{\mathit N}$
 (${\mathit \mu}_{{{\mathit p}}}$ $+$ ${\mathit \mu}_{{{\overline{\mathit p}}}}$) $/$ $\mu _{{{\mathit p}}}$ $(2 \pm4) \times 10^{-9}$
 ${{\mathit p}}$ ELECTRIC DIPOLE MOMENT $<2.1 \times 10^{-25}$ $\mathit e~$cm
 ${{\mathit p}}$ ELECTRIC POLARIZABILITY ${{\mathit \alpha}_{{p}}}$ $0.00112 \pm0.00004$ fm${}^{3}$
 ${{\mathit p}}$ MAGNETIC POLARIZABILITY ${{\mathit \beta}_{{p}}}$ $(2.5 \pm0.4) \times 10^{-4}$ fm${}^{3}$ (S = 1.2)
 ${{\mathit p}}$ CHARGE RADIUS $0.8409 \pm0.0004$ fm
 ${{\mathit p}}$ MAGNETIC RADIUS $0.851 \pm0.026$ fm
 ${{\mathit p}}$ MEAN LIFE $>3.6 \times 10^{29}$ years  CL=90.0%
 ${{\overline{\mathit p}}}$ MEAN LIFE
See the Note on Nucleon Decay'' in our 1994 edition (Phys. Rev. $\mathbf {D50}$, 1173) for a short review.
The partial mean life'' limits tabulated here are the limits on ${{\mathit \tau}}/B_{\mathit i}$, where ${{\mathit \tau}}$ is the total mean life and B$_{\mathit i}$ is the branching fraction for the mode in question. For ${{\mathit N}}$ decays, ${{\mathit p}}$ and ${{\mathit n}}$ indicate proton and neutron partial lifetimes.