English

Perturbations to $\mu-\tau$ reflection symmetry due to renormalization group running effects

High Energy Physics - Phenomenology 2025-10-16 v1

Abstract

μτ\mu-\tau reflection symmetry is an attractive flavour symmetry in lepton mixing, which accommodates maximal values of atmospheric mixing angle (θ23=π/4\theta_{23}=\pi/4) and Dirac CP phase (δ=π/2/3π/2\delta=\pi/2/3\pi/2). Another significance of this symmetry is that it does not constrain θ13\theta_{13} to be zero. As the recent results from T2KT2K and NOνANO\nu A experiments indicate a near-maximal value of the Dirac CP phase, the role of μτ\mu-\tau reflection symmetry becomes more prominent. In this work, we study RG running effects as a perturbation to the μτ\mu-\tau reflection symmetry. Assuming the symmetry to be preserved at the seesaw scale, we study the deviations of mass eigenvalues and lepton mixing parameters at the electroweak scale due to RG running. We derive the one-loop RGEs of the mass eigenvalues and mixing parameters and solve them numerically. Numerical analysis shows that the deviations from μτ\mu-\tau reflection symmetry are consistent with 3σ3\sigma range of global oscillation data.

Keywords

Cite

@article{arxiv.2510.13585,
  title  = {Perturbations to $\mu-\tau$ reflection symmetry due to renormalization group running effects},
  author = {Chandan Kumar Borah and Chandan Duarah},
  journal= {arXiv preprint arXiv:2510.13585},
  year   = {2025}
}