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

TL;DR

This paper discusses the feasibility of a next-generation European neutrino observatory using a high-intensity proton source at CERN, aiming to study neutrino oscillations, mass hierarchy, and CP-violation with a multi-MW superbeam.

Contribution

It presents a detailed technical design and assessment of a high-energy proton source and superbeam for long baseline neutrino experiments in Europe, including site evaluation and physics goals.

Findings

Feasibility of a high-intensity proton source at CERN.

Potential to measure neutrino mass hierarchy and CP-violation.

Identification of suitable underground sites for the detector.

Abstract

The feasibility of a European next-generation very massive neutrino observatory in seven potential candidate sites located at distances from CERN ranging from 130 km to 2300 km, is being considered within the LAGUNA design study. The study is providing a coordinated technical design and assessment of the underground research infrastructure in the various sites, and its coherent cost estimation. It aims at a prioritization of the sites within summer 2010 and a start of operation around 2020. In addition to a rich non-accelerator based physics programme including the GUT-scale with proton decay searches, the detection of a next-generation neutrino superbeam tuned to measure the flavor-conversion oscillatory pattern (i.e. 1st and 2nd oscillation maxima) would allow to complete our understanding of the leptonic mixing matrix, in particular by determining the neutrino mass hierarchy and by studying CP-violation in the leptonic sector, thereby addressing the outstanding puzzle of the origin of the excess of matter over antimatter created in the very early stages of evolution of the Universe. We focus on a multi-MW-power neutrino superbeam (="hyperbeam") produced by high-intensity primary protons of energy 30$\div$50 GeV. We argue that this option is an effective way to establish long baseline neutrino physics in Europe with the high-stake prospects of measuring $\theta_{13}$ and addressing CP-violation in the leptonic sector.