Identifying a minimal flavor symmetry of the seesaw mechanism behind neutrino oscillations

Abstract

In the canonical seesaw framework flavor mixing and CP violation in weak charged-current interactions of light and heavy Majorana neutrinos are correlated with each other and described respectively by the $3\times 3$ matrices $U$ and $R$. We show that the very possibility of $\left|U_{\mu i}^{}\right|=\left|U_{\tau i}^{}\right|$ (for $i=1,2,3$), which is strongly indicated by current neutrino oscillation data, automatically leads to a novel prediction $\left|R_{\mu i}^{}\right|=\left|R_{\tau i}^{}\right|$ (for $i=1,2,3$). We prove that behind these two sets of equalities and the experimental evidence for leptonic CP violation lies a minimal flavor symmetry -- the overall neutrino mass term keeps invariant when the left-handed neutrino fields transform as ${\nu }_{e\mathrm{L}}^{}\to ({\nu }_{e\mathrm{L}}^{}{)}^c$, ${\nu }_{\mu \mathrm{L}}^{}\to ({\nu }_{\tau \mathrm{L}}^{}{)}^c$, ${\nu }_{\tau \mathrm{L}}^{}\to ({\nu }_{\mu \mathrm{L}}^{}{)}^c$ and the right-handed neutrino fields undergo an arbitrary unitary CP transformation. Such a generalized $\mu$-$\tau$ reflection symmetry may help constrain the flavor textures of active and sterile neutrinos to some extent in the seesaw mechanism.

LaTeX 16 pages, 2 figures. More discussions and references added. Accepted for publication in JHEP

References in corpus (14)

• Observation of electron-antineutrino disappearance at Daya Bay
• The fate of hints: updated global analysis of three-flavor neutrino oscillations
• Unitarity of the Leptonic Mixing Matrix
• Correlation between the Charged Current Interactions of Light and Heavy Majorana Neutrinos
• Complete One-loop Matching of the Type-I Seesaw Model onto the Standard Model Effective Field Theory
• Low-energy limits on heavy Majorana neutrino masses from the neutrinoless double-beta decay and non-unitary neutrino mixing
• Global oscillation data analysis on the $3\nu$ mixing without unitarity
• Non-unitary Leptonic Flavor Mixing and CP Violation in Neutrino-antineutrino Oscillations
• Radiative Decays of Charged Leptons in the Seesaw Effective Field Theory with One-loop Matching
• A combination of the neutrino trimaximal mixings and mu-tau reflection symmetry in the type-I seesaw model
• Radiative decays of charged leptons as constraints of unitarity polygons for active-sterile neutrino mixing and CP violation
• Seesaw mirroring between light and heavy Majorana neutrinos with the help of the $S_3^{}$ reflection symmetry
• Renormalization group evolution induced leptogenesis in the minimal seesaw model with the trimaximal mixing and mu-tau reflection symmetry
• Particular textures of the minimal seesaw model

Cited by in corpus (1)

• The $\mu$-$\tau$ reflection symmetry of Majorana neutrinos