Search for CP violation in the lepton sector

TL;DR

This paper reviews the search for CP violation in the neutrino sector, focusing on beta-beam facilities and astrophysical environments like supernovae, highlighting current proposals, feasibility, and potential effects on nucleosynthesis.

Contribution

It provides a comprehensive review of beta-beam scenarios and explores the possibility of detecting CP violation effects in supernovae environments.

Findings

Beta-beam scenarios vary in feasibility and design.

CP violation effects can influence supernova neutrino fluxes.

Conditions for CP violation in dense media are identified.

Abstract

One of the major open issues in neutrino physics is the possible existence of CP violation in the neutrino sector. Such an observation would have an important impact in various domains of physics, from high energy physics to cosmology. Its search requires future accelerator neutrino facilities producing intense and pure neutrino beams such as "beta-beams". Here we review the different beta-beam scenarios proposed so far and discuss the present status, with a particular emphasis on the original baseline scenario and its feasibility. Alternative strategies for the CP violation search are to be pursued as well. A possibility is to search for CP violation effects in astrophysical environments. Here we present recent analytical and numerical results obtained in the context of core-collapse supernovae. In particular, we point out the conditions under which there can be CP violating effects in dense media and show numerical results on the supernova (anti-)neutrino fluxes and on the electron fraction, relevant for the r-process nucleosynthesis.