arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1802.04563hep-ph
收藏

具有最大限制纹理零点的最小I型跷跷板模型

The minimal type-I seesaw model with maximally-restricted texture zeros

D. M. Barreiros, R. G. Felipe, F. R. Joaquim

摘要:

在标准模型(SM)扩展的背景下,跷跷板机制为中微子质量的微小提供了最自然的解释。在这项工作中,我们考虑最经济的I型跷跷板实现中,两个右手中微子被添加到SM场的内容。为了可预测性,我们施加的轻子汤川和质量矩阵的纹理零点的最大数量。根据最新的中微子振荡数据分析了所有可能的模式,并提出了轻子CP破坏的预言。我们的结论是,在带电轻子质量的基础上,八种不同的纹理组合是兼容的中微子数据在$1σ$,所有这些都是一个倒置的层次中微子质谱。其中四种情况预测CP破坏狄拉克相位接近$3π/2$,这是目前最好的拟合值从全球分析的中微子振荡数据。如果考虑狄拉克中微子汤川耦合矩阵中的三个相等元素,进一步减少自由参数的数量,则几种纹理组合仍然与数据相容,但仅在$3σ$处。对于所有可行的纹理,宇宙的重子不对称性计算的热leptogenesis的背景下,假设(轻度)分级重马约拉纳中微子质量$M_{1,2}$。结果表明,风味政权被排除在外,而unflavored一个需要$M_{1} \sim 10^{14}$ GeV。

英文摘要:

In the context of Standard Model (SM) extensions, the seesaw mechanism provides the most natural explanation for the smallness of neutrino masses. In this work we consider the most economical type-I seesaw realization in which two right-handed neutrinos are added to the SM field content. For the sake of predictability, we impose the maximum number of texture zeros in the lepton Yukawa and mass matrices. All possible patterns are analyzed in the light of the most recent neutrino oscillation data, and predictions for leptonic CP violation are presented. We conclude that, in the charged-lepton mass basis, eight different texture combinations are compatible with neutrino data at $1σ$, all of them for an inverted-hierarchical neutrino mass spectrum. Four of these cases predict a CP-violating Dirac phase close to $3π/2$, which is around the current best-fit value from global analysis of neutrino oscillation data. If one further reduces the number of free parameters by considering three equal elements in the Dirac neutrino Yukawa coupling matrix, several texture combinations are still compatible with data but only at $3σ$. For all viable textures, the baryon asymmetry of the Universe is computed in the context of thermal leptogenesis, assuming (mildly) hierarchical heavy Majorana neutrino masses $M_{1,2}$. It is shown that the flavored regime is ruled out, while the unflavored one requires $M_{1} \sim 10^{14}$ GeV.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑