European facilities for accelerator neutrino physics: perspectives for the decade to come

TL;DR

This paper reviews European neutrino research facilities and explores future prospects for measuring CP violation and other phenomena in neutrino physics, emphasizing European contributions and potential exotic scenarios.

Contribution

It summarizes the current status of European neutrino facility studies and discusses options leveraging existing infrastructure and emerging technologies for future research.

Findings

European facilities like CERN and Gran Sasso are central to future neutrino research.

Potential for new experiments to measure CP violation in the neutrino sector.

Consideration of beyond-standard-model scenarios based on recent experimental hints.

Abstract

Very soon a new generation of reactor and accelerator neutrino oscillation experiments - Double Chooz, Daya Bay, Reno and T2K - will seek for oscillation signals generated by the mixing parameter theta_13. The knowledge of this angle is a fundamental milestone to optimize further experiments aimed at detecting CP violation in the neutrino sector. Leptonic CP violation is a key phenomenon that has profound implications in particle physics and cosmology but it is clearly out of reach for the aforementioned experiments. Since late 90's, a world-wide activity is in progress to design facilities that can access CP violation in neutrino oscillation and perform high precision measurements of the lepton counterpart of the Cabibbo-Kobayashi-Maskawa matrix. In this paper the status of these studies will be summarized, focusing on the options that are best suited to exploit existing European facilities (firstly CERN and the INFN Gran Sasso Laboratories) or technologies where Europe has a world leadership. Similar considerations will be developed in more exotic scenarios - beyond the standard framework of flavor oscillation among three active neutrinos - that might appear plausible in the occurrence of anomalous results from post-MiniBooNE experiments or the CNGS.