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Possible new source of $T$ and $C P$ violation in neutrino oscillations

Institute for Theoretical Physics, University of Karlsruhe (TH), 76128 Karlsruhe, Germany

^*Electronic address:frans.klinkhamer@physik.uni-karlsruhe.de

Phys. Rev. D 73, 057301 – Published 1 March, 2006

DOI: https://doi.org/10.1103/PhysRevD.73.057301

Abstract

A model is presented to illustrate that vacuum neutrino oscillations can be essentially $T$ and $C P$ invariant up to a certain energy but strongly $T$ and $C P$ noninvariant at much higher energies. Detailed model results for the vacuum probabilities $P (ν_{μ} \to ν_{e})$ and $P (ν_{e} \to ν_{μ})$ are given, which may be relevant to proposed long-baseline neutrino-oscillation experiments.

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References (30)

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The notation of the neutrino dispersion relation in Refs. [5,6] differs from the one used here and in Ref. [7], but the different sign of $b_{0}^{(f)}$ can be compensated by a sign change of the complex phase $ϵ$ . For example, setting $ϵ = - ω$ in the exact model probability $P (ν_{μ} \to ν_{e})$ from Eq. (11e) in Ref. [6] reproduces the numerical $ρ \to \infty$ results for $R = 1$ , $ω = χ_{21} = χ_{32} = π / 4$ , and $χ_{13} = \arctan \sqrt{1 / 2} \approx π / 5$ (these numerical results resemble those of Fig. 1 for $χ_{13} = π / 4$ ).
Degenerate perturbation theory for $ρ \to 0$ and fixed $τ$ (arbitrary $R$ and $ω$ ) gives $P_{μ e} \sim (4 R^{2} / S) {sin }^{2} [\sqrt{S} τ / (8 + 8 R)]$ with $S \equiv 4 + 4 R + 9 R^{2}$ .
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Super-Kamiokande data, interpreted with a pure Fermi-point-splitting model, may hint at a nonzero value of the complex phase, as argued in footnote b of Ref. [6].
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D. S. Ayres et al. (NOνA Collaboration), hep-ex/0503053.

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Possible new source of $T$ and $C P$ violation in neutrino oscillations

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Possible new source of T and CP violation in neutrino oscillations

Abstract

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References (30)

Possible new source of $T$ and $C P$ violation in neutrino oscillations