# Wu experiment and masses of neutrino

Wu experiment have shown that there are only left-handed neutrinos (and right-handed antineutrinos) take part in weak interactions. My question is about the significance of this experiment in a historical question about neutrino masses.

There is possible that there exist both left and right neutrinos, but only left neutrino takes part in weak interactions (i.e., there is left doublet $\begin{pmatrix} l & \nu_{l}\end{pmatrix}_{L}$ and right singlet $\begin{pmatrix}l \end{pmatrix}_{R}$ under $SU_{W}(2)$ group). On the other side, it is known that only massless and massive Majorana states may have definite helicity, and no mass of neutrino was observed. Thus for case of massless neutrino we don't need to deal with right neutrino.

So have Wu experiment somehow affected on the historical point of view that neutrinos are massless?