Neutrino Physics Related to Long Baseline Experiments

我讨论了在中微子工厂测量CP破坏的可能性。当地球密度的不确定度大于10%或背景/信号比大于10^时，对于基线小于1000 km和μ子能量小于20 GeV的情况，信号是最佳的<-3>。我证明了，在长基线实验中，如果基线很短，物质效应对二阶非平凡阶是可以忽略的。使用相同的形式主义，我推导出了在恒定密度和恒定磁场中，对于任意数量的味道，振荡概率的解析公式。我建议用反应堆中微子测量第三混合角θ_<13>。我表明，反应堆中微子的方法起着补充加速器实验的作用，一些参数简并可以通过结合它们来解决。我还讨论了对sin ^2 2θ_的灵敏度<13>，考虑到由于多反应堆的性质等引起的各种系统误差。我发现，在柏崎计划的情况下，对sin ^2 2θ_的灵敏度<13>约为0.02，对于任何反应堆实验，最好的灵敏度约为0.01。我讨论了在JPARC测量中微子和反中微子后，如何通过实验解决参数简并，使用（sin^2 2θ_<13>，1/s^2_<23>）平面中的新图。我发现，如果低能方案在JPARC或离轴NuMI实验上是可能的，那么它可以解决θ_<23>惠π-δ和Δm^2_<31>惠-Δm^2_的模糊性<31>。我证明了ν_e → ν_τ的测量也是有用的。

I discussed the possibility of measurement of CP violation at a neutrino factory. I showed that the signal is optimized for the baseline less than 1000km and the muon energy less than 20GeV, if the uncertainty of the density of the Earth is more than 10% or if the background/signal ratio is more than 10^<-3>. I showed that the matter effect is negligible to the second nontrivial orders in long baseline experiments, if the baselines are short. Using the same formalism I derived the analytical formula for the oscillation probability in the matter with constant density and in a constant magnetic field for the arbitrary numbers of flavors. I proposed to measure the third mixing angle θ_<13> using reactor neutrinos. I showed that the reactor neutrino method plays a role complementary to accelerator experiments and that some of parameter degeneracy can be resolved by combining them. I also discussed the sensitivity to sin^2 2θ_<13>, taking into account various kinds of systematic errors due to the nature of multiple reactors etc. I found hat the sensitivity to sin^2 2θ_<13> is about 0.02 in the case of the Kashiwazaki plan, and can be about 0.01 for any reactor experiment at best. I discussed how parameter degeneracy can be resolved by an experiment after the JPARC measurements of neutrinos and anti-neutrinos, using the new plot in the (sin^2 2θ_<13>, 1/s^2_<23>) plane. I found that, if low energy option is experimentaly possible at JPARC or off axis NuMI, then it could resolve the ambiguities of θ_<23> ⇔ π-δ, and Δm^2_<31> ⇔ -Δm^2_<31>. I showed that measurement of ν_e → ν_τ is also useful.