分类: 物理学 >> 普通物理:统计和量子力学,量子信息等 提交时间: 2017-11-10
摘要: The neutrinoless double-beta (0ν2β) decay is currently the only feasible process in particle and nuclear physics to probe whether massive neutrinos are the Majorana fermions. If they are of the Majorana nature and have a normal mass ordering, the effective neutrino mass term mee of a 0ν2β decay may suffer significant cancellations among its three components and thus sink into a decline,resulting in a “well” in the three-dimensional graph of |mee| against the smallest neutrino mass m1 and the relevant Majorana phase ρ. We present a new and complete analytical understanding of the fine issues inside such a well, and identify a novel threshold of |mee| in terms ofthe neutrino masses and flavor mixing angles: |mee|∗ = m3 sin2 θ13 in connection with tan θ12 = m1/m2 and ρ = π. This threshold point, which links the local minimum and maximum of |mee|, can be used to signify observability or sensitivity of the future 0ν2β-decay experiments. Given current neutrino oscillation data, the possibility of |mee| < |mee|∗ is found to be very small.
分类: 物理学 >> 核物理学 提交时间: 2016-09-18
摘要: Behind the observed pattern of lepton flavor mixing is a partial or approximate mu-tau flavor symmetry --- a milestone on our road to the true origin of neutrino masses and flavor structures. In this review article we first describe the features of mu-tau permutation and reflection symmetries, and then explore their various consequences on model building and neutrino phenomenology. We pay particular attention to soft mu-tau symmetry breaking, which is crucial for our deeper understanding of the fine effects of flavor mixing and CP violation.
分类: 物理学 >> 核物理学 提交时间: 2016-09-05
摘要: The latest LHC data suggest an intriguing excess at mγγ=750 GeV which apparently requires an explanation from the beyond standard model physics. In this note we explore the possibility for this signal to arise from a top-pion in the Top Triangle Moose model which can be viewed as a dimensional-deconstruction version of the top-color assisted technicolor model. We demonstrate that the observed excess can be accommodated by and has important implications for this interesting model.