2022/01/25 by Chatterjee, Sabya Sachi, Palazzo, Antonio
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2201.10412
The current data of the two long-baseline accelerator experiments NOνA and T2K, shows a tension at more than 90% C.L. for 2 degrees of freedom, in the determination of the standard CP-phase δ_\mathrm CP in case of neutrino normal ordering (NO). NOνA measures the value close to δ_\mathrm CP ∼ 0.8 π, while T2K prefers the value of δ_\mathrm CP ∼ 1.4 π. We show that such a tension can be resolved if one hypothesizes the existence of neutral-current non-standard interactions (NSI) of neutrinos involving the flavor changing type e-μ or the e-τ sectors with couplings |εeμ| ∼ |εeτ|∼ 0.2. Remarkably, our analyses show that in the presence of such NSI, both the experiments point towards the same common value of the standard CP-phase δ_\mathrm CP ∼ 3π/2, thereby indicating towards the maximal CP-violation in the standard 3ν framework. We also show that the best fit values of the new CP-phases ϕeμ or ϕeτ are close to ∼ 3π/2, hence pointing towards the maximal CP-violation in the NSI sector.