A CERN-based high-intensity high-energy proton source for long baseline neutrino oscillation experiments with next-generation large underground detectors for proton decay searches and neutrino physics and astrophysics

摘要

The feasibility of a European next-generation very massive neutrinoobservatory in seven potential candidate sites located at distances from CERNranging from 130 km to 2300 km, is being considered within the LAGUNA designstudy. The study is providing a coordinated technical design and assessment ofthe underground research infrastructure in the various sites, and its coherentcost estimation. It aims at a prioritization of the sites within summer 2010and a start of operation around 2020. In addition to a rich non-acceleratorbased physics programme including the GUT-scale with proton decay searches, thedetection of a next-generation neutrino superbeam tuned to measure theflavor-conversion oscillatory pattern (i.e. 1st and 2nd oscillation maxima)would allow to complete our understanding of the leptonic mixing matrix, inparticular by determining the neutrino mass hierarchy and by studyingCP-violation in the leptonic sector, thereby addressing the outstanding puzzleof the origin of the excess of matter over antimatter created in the very earlystages of evolution of the Universe. We focus on a multi-MW-power neutrinosuperbeam (="hyperbeam") produced by high-intensity primary protons of energy30$\div$50 GeV. We argue that this option is an effective way to establish longbaseline neutrino physics in Europe with the high-stake prospects of measuring$\theta_{13}$ and addressing CP-violation in the leptonic sector.