The observed pattern of lepton flavor mixing and CP violation strongly indicates the possible existence of a simple flavor symmetry in the neutrino sector—the effective Majorana neutrino mass term keeps invariant when the three left-handed neutrino fields transform as νeL→(νeL)c , νμL→(ντL)c and ντL→(νμL)c . A direct application of such a µ–τ reflection symmetry to the canonical seesaw mechanism can help a lot to constrain the flavor textures of active and sterile Majorana neutrinos. The present article is intended to summarize the latest progress made in exploring the properties of this minimal flavor symmetry, its translational and rotational extensions, its soft breaking effects via radiative corrections from a superhigh energy scale to the electroweak scale, and its various phenomenological implications.

中文翻译：

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马约拉纳中微子的 µ–τ 反射对称性 *

观察到的轻子味混合和 CP 破坏模式强烈表明中微子扇区可能存在简单的味对称性——当三个左手中微子场变换为时，有效马约拉纳中微子质量项保持不变 ν电子大号→(ν电子大号)C , νμ大号→(ντ大号)C 和 ντ大号→(νμ大号)C . 直接应用这样的µ–τ典型跷跷板机制的反射对称性可以极大地帮助约束活跃和惰性马约拉纳中微子的味道质地。本文旨在总结在探索这种最小味对称性的性质、其平移和旋转扩展、其通过从超高能量尺度到电弱尺度的辐射校正的软破断效应及其各种现象学意义方面取得的最新进展。