Bibliographic Details
| Title: |
Biprobability approach to CP phase degeneracy from non-standard neutrino interactions |
| Authors: |
Hyde, Jeffrey M. |
| Source: |
Nuclear Physics B 949 (2019) 114804 |
| Publication Year: |
2018 |
| Collection: |
High Energy Physics - Phenomenology |
| Subject Terms: |
High Energy Physics - Phenomenology |
| More Details: |
Non-standard interactions (NSI) between neutrinos and matter at long-baseline experiments could make determination of the CP-violating phase $\delta_{13}$ ambiguous due to interference with additional complex phases. Such degeneracies are often studied in the context of specific experiments and a few parameter choices, leaving it unclear how to extract a general understanding of when two sets of parameters may be degenerate or how different types of experiments in principle combine to lift such a degeneracy. This work complements detailed simulations of individual experiments by showing how underlying parameters relate to degeneracies as represented on a biprobability plot. We show how a range of energies near the oscillation maximum $\Delta_{31} = \pi/2$ separates some degenerate probabilities along the CP-conserving direction of biprobability space according to $\delta_{+} \equiv \delta_{13} + \delta_{e\tau}$, while near $\Delta_{31} = 3\pi/2$ degenerate probabilities are separated along the CP-violating direction according to $\delta_{e\tau}$. We apply this to the experimental hints that suggest $\delta_{13} \sim -\pi/2$ to see that this could also be consistent with $\delta_{13}, \delta_{e\tau} = 0$ or $\pi$. The baseline and energy range characteristic of DUNE provides some resolution, but a further improvement comes from beams a few degrees off-axis at $\gtrsim 1000$ km baselines, including some proposed sites for T2HKK.
Comment: Version accepted & to appear in Nuclear Physics B |
| Document Type: |
Working Paper |
| DOI: |
10.1016/j.nuclphysb.2019.114804 |
| Access URL: |
http://arxiv.org/abs/1806.09221 |
| Accession Number: |
edsarx.1806.09221 |
| Database: |
arXiv |
