# Have all three flavors of solar neutrino been measured?

As far as I know that the sun exclusively produces electron neutrinos ($\nu_e$). When the flux of solar neutrinos ($\nu_e$) is measured on the earth, a depletion is observed in the $\nu_e$ flux i.e., some $\nu_e$'s have "disappeared" in their way from the sun to the earth. As far as I know that this conclusion is drawn, by measuring only$^1$ the $\nu_e$ flux in the detectors. The explanation is that some of the neutrinos get morphed into $\nu_\mu$ and $\nu_\tau$.

But to really test this hypothesis, a deficiency in the $\nu_e$ flux is not enough. There must be an experiment where the detector must also measure the $\nu_\mu$ and $\nu_\tau$ fluxes. If adding the fluxes over all three flavors turns out to be equal to the expected flux then only we can be sure that solar neutrinos have undergone oscillation. Has that been achieved in experiments?

$^1$The experiment carried out by Davis et al at the Homestake mines detected $\nu_e$ through the inverse beta decay $\nu_e+^{37}{\rm Cl}\to e^-+^{37}{\rm Ar},$ and found that they were getting about one-third of the number of $\nu_e$ that were predicted from the solar models.

• One of my answers to a previous question that you asked exhibits the mechanism by which SNO disentangles the electron-type from heavy-lepton-type neutrinos. Jul 14 '18 at 16:43