Investigation of Long Baseline Neutrino Oscillations from Experiments at KAON

Abstract

The proposed KAON factory at the Triumf Laboratory in Vancouver, Canada provides a unique opportunity for high statistics long baseline neutrino oscillation experiments. Several possibilities are under active consideration. In this paper we describe the theoretical expectations for a {\it very} long baseline experiment in which the neutrinos are directed towards, and detected at the Superkamiokande detector in Kamioka, Japan 7200 km away. We find that in the first year this experiment would probe oscillations down to about $\Delta m^2_0 = 9 \times 10^{-5} eV^2$ for maximal mixing, and if $\Delta m^2_0 \geq 5 \times 10^{-4} eV^2$ it would be sensitive to $sin^2(2 \theta_0) \geq 0.2$. These results are compared with a more modest proposal of a 100 km baseline with a 6300 tonne detector which would probe $\Delta m^2_0 \geq 1.3 \times 10^{-3} eV^2$ for maximal mixing, and if $\Delta m^2_0 \geq 0.02 eV^2$ it would be sensitive to $sin^2(2 \theta_0) \geq 0.01$. These experiments would either confirm or rule out the entire range of parameters allowed by Kamiokande and IMB to explain the deficit in the ratio of $\nu_\mu$ to $\nu_e$ in current atmospheric neutrino experiments. The Kamiokande experiment would also investigate matter enhanced neutrino oscillations (the MSW effect) down to about $\Delta m^2 = 3 \times 10^{-4} eV^2$.