Method of Measuring the Beta-Decay Coupling Constant of the Rho Meson

It is proposed that one measure the diffraction production of the $\rho$ meson by high-energy neutrinos, i.e., the process $\nu \to {\mu }^{-}+{{\rho }_{\mathrm{virtual}}}^{+}$ followed by ${\rho }^{+}$ diffraction scattering. By comparison with $\gamma +p\to {\rho }^0+p$, the $\beta$-decay coupling constant can then be obtained. The process is distinguishable experimentally because of the characteristic low momentum transfer to the nucleon. Numerical calculations indicate that this process should be observable in large heavy-liquid bubble chambers.