Determining the yet unknown neutrino parameters from future oscillation experiments

por Dr. Hiroshi Nunokawa (Pontificia Universidade Catolica do Rio de Janeiro)

viernes 20 feb. 2004 12:00 → 13:00 Europe/Madrid

Sala Seminarios IFIC (Edf. Institutos de Investigación)

Assuming 3 neutrinos with CPT invariance (ignoring LSND), we already have significant amount of information on neutrino mass spectrum and mixing angles. The remaining important quantities which are not yet unknown but can be probed by future oscillation experiments are 1) value of $\theta_{13}$ (how small?), 2) sign of $\Delta m^2_{13}$, and 3) CP violating phase, $\delta$. In principle, all of them can be determined by the future long-baseline oscillation experiments. However, it is known that determination of these quantities suffer from the problem of so called parameter degeneracy which could lead up to 8 solutions which give exactly the same probabilities for neutrino and anti-neutrino for a given energy and baseline. I will give an overview of this problem and discuss some possible way way to lift the degeneracy. I will address that the reactor oscillation experiment which aim to measure $\theta_{13}$ can help in lifting this degeneracy.