We present a new texture of neutrino mass matrix having three complex relations among its elements and study in detail the phenomenological implications. A characteristic feature of the resulting neutrino mass matrix is that the atmospheric neutrino mixing angle is predicted to lie in a very narrow region near ${45}^{\circ }$. We illustrate how such a form of the neutrino mass matrix can be realized using the non-Abelian flavor symmetry $A_4$ in the framework of type-I+II seesaw mechanism.

中文翻译：

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具有三个约束的中微子质量矩阵的新纹理

我们提出了一种新的中微子质量矩阵结构，其元素之间具有三个复杂的关系，并详细研究了现象学的含义。由此产生的中微子质量矩阵的一个特征是大气中微子混合角预计位于靠近${45}^{\circ }$. 我们说明了如何使用非阿贝尔风味对称性来实现这种形式的中微子质量矩阵${\mathrm{一种}}_4$ 在I+II型跷跷板机制的框架内。