頁籤選單縮合
題 名 | Model of the Neutrino Mass Matrix with δ=−π/2 and θ23=π/4 |
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作 者 | He, Xiao-gang; | 書刊名 | Chinese Journal of Physics |
卷 期 | 53:5 2015.10[民104.10] |
頁 次 | 頁(100202)1-(100202)9 |
分類號 | 331.311 |
關鍵詞 | |
語 文 | 英文(English) |
英文摘要 | Experimental data have provided stringent constraints on the neutrino mixing parameters. In the standard parameterization the mixing angle θ_(23) is close to π/4. There is also evidence which shows that the CP violating phase is close to -π/2. We study the neutrino mass matrix reconstructed using this information and find several interesting properties. We show that a theoretical model based on the A_4 symmetry naturally predicts δ = -π/2 and θ_(23) = π/4 when the Yukawa couplings and scalar vacuum expectation values are real, reaching a μ-τ exchange and CP conjugate symmetry limit. In this case CP violation solely comes from the complex group theoretical Clebsh-Gordan coefficients. The model also predicts |V_(e2)| = 1/√3, consistent with the data. With complex Yukawa couplings the values for δ and θ_(23) can significantly deviate away from the symmetry values -π/2 and π/4, respectively. But |V_(e2)| = 1/√3 is not altered. This matrix is an excellent lowest order approximation for theoretical model buildings of the neutrino mass matrix. |
本系統中英文摘要資訊取自各篇刊載內容。