Abstract
The possible existence of light and heavy sterile neutrinos may give rise to direct and indirect unitarity violation of the 3×3 lepton mixing matrix respectively. In the current work we study the potential of future accelerator neutrino facilities in probing the unitarity violation effects. Taking DUNE, T2HK and a low-energy Neutrino Factory (LENF) as working examples of future accelerator neutrino facilities, we study the distinct effects of direct and indirect unitarity violation on the discovery reach of the leptonic CP violation and precision measurements of θ23 in the three neutrino framework. In addition, constraints on the additional mixing parameters of direct and indirect unitarity violation are also discussed. Finally, we stress that the combination of experiments with different oscillation channels, different neutrino beams and different detector techniques will be an effective solution to the parameter degeneracy problem and give the robust measurement of leptonic CP violation even if the direct and indirect unitarity violation are taken into account.
Highlights
The experimental establishment of neutrino oscillations [1, 2] requires non-zero neutrino masses and non-trival lepton mixing
We carry out the analyses with two different hypotheses: the direct unitarity violation (DUV) case and the DUV+indirect unitarity violation (IUV) case
Based on the above simulation results, we briefly summarize the feature of the impact from DUV and IUV effects
Summary
The experimental establishment of neutrino oscillations [1, 2] requires non-zero neutrino masses and non-trival lepton mixing. When sterile neutrinos are heavy and kinematically forbidden in the neutrino production and detection processes, they only have indirect effects on the 3 × 3 PMNS matrix, which is defined as indirect unitarity violation (IUV) [21, 23, 26, 28, 29]. When the sterile neutrinos are light and participate in the neutrino production, oscillation and detection processes, their direct effects on the the 3 × 3 PMNS matrix will be very different from the heavy case. We define this scenario as the direct unitarity violation (DUV) [21, 23, 26, 28, 29].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
