推广的双跷跷板模型下的中微子质量及模型分类

Neutrino Masses in the Extended Double Seesaw Model and Its Classification

在推广的双跷跷板模型下,给出了轻中微子质量矩阵的一般形式,并且指出传统的第一类跷跷板模型(Type-I Seesaw)和双跷跷板模型(Double Seesaw)是推广的双跷跷板模型的两种特殊情况.通过分析这种模型的中微子9×9质量矩阵,发现当MR=MSMμ1MST严格成立时,推广的双跷跷板模型会退化到传统的第一类跷跷板模型.通过研究MS,Mμ和MR的秩和矩阵结构,推广的双跷跷板模型一共可以被分为105类,并且研究了它的最小模型,即仅有两代轻中微子的情况.还研究了推广的双跷跷板模型的幺正性破坏.

We give the general form of light neutrino mass matrix in the Extended Double Seesaw Model （EDSM）, and also demonstrate that the conventional type-1 and double seesaw mechanisms can be regarded as two special cases of the EDSM. The structure of the 9 × 9 neutrino mass matrix in this scenario is analyzed, and we find that the EDSM will degenerate to the conventional type-I seesaw mechanism when MR ： MsMu-1MS^T hold exactly. We find that the EDSM can be classified into 105 classes according to the rank and structure of Ms, Mu and MR, and we study its minimal form, which only has two generations. We also discuss the non-unitary effects in EDSM.