Possible CP-violation effects in core-collapse supernovae

A.B Balantekin,J Gava,C Volpe

doi:10.1016/j.physletb.2008.03.038

A.B Balantekin, J Gava + Show 1 more

Open Access

https://doi.org/10.1016/j.physletb.2008.03.038

Copy DOI

Abstract

We study CP-violation effects when neutrinos are present in dense matter, such as outside the proto-neutron star formed in a core-collapse supernova. Using general arguments based on the Standard Model, we confirm that there are no CP-violating effects at the tree level on the electron neutrino and anti-neutrino fluxes in a core-collapse supernova. On the other hand significant effects can be obtained for muon and tau neutrinos even at the tree level. We show that CP-violating effects can be present in the supernova electron (anti-)neutrino fluxes as well, if muon and tau neutrinos have different fluxes at the neutrinosphere. Such differences could arise due to physics beyond the Standard Model, such as the presence of flavor-changing interactions.

Highlights

Recent results from solar, atmospheric and reactor experiments have significantly improved our knowledge of the neutrino mass differences and of two of the mixing angles
The purpose of the present paper is to explore possible effects coming from the CP-violating phase in dense matter, such as that encountered in core-collapse supernovae
POSSIBLE CP VIOLATION EFFECTS: NUMERICAL RESULTS. It is the goal of this section to investigate numerically effects induced by the Dirac δ phase : i) on the muon and tau neutrino fluxes when their fluxes at the neutrinosphere are supposed to be equal; ii) on the electron, muon, tauneutrino fluxes, when the muon and neutrino fluxes differ at the neutrinosphere

Summary

Introduction

Recent results from solar, atmospheric and reactor experiments have significantly improved our knowledge of the neutrino mass differences and of two of the mixing angles. If the remaining mixing angle, θ13, is relatively large there is a possibility that violation of CP symmetry may be observable in the neutrino sector. Effects of CP-violation in accelerator neutrino oscillation experiments have been extensively investigated [4, 5, 6, 7, 8, 9]. Besides studies on terrestrial experiments with man-made sources, a few recent works have addressed CP-violation with neutrinos from astrophysical sources The purpose of the present paper is to explore possible effects coming from the CP-violating phase in dense matter, such as that encountered in core-collapse supernovae

Objectives

Results

Conclusion