Invited talk at the XXth Internat. Conf. on Neutrino Physics and Astrophysics (Neutrino 2002), Munich, Germany, May 25-30, 2002. 12 pages, 18 figs, includes espcrc2.sty
I review the interpretation of solar and atmospheric neutrino data in terms neutrino oscillations and describe some ways to account for the required neutrino masses and mixing angles from first principles, both within top-down and bottom-up approaches. I also discuss non-oscillation phenomena such as nu-less double beta which may probe the absolute scale of neutrino mass, and also reveal its Majorana nature. I note that leptonic CP violation induced by ``Majorana'' phases drop from oscillations but play a role in the leptogenesis scenario for the baryon asymmetry of the Universe. Direct tests of leptonic CP violation in oscillation experiments, such as neutrino factories, will be a tough challenge, due to the hierarchical neutrino mass splittings and the smallness of theta13 indicated by reactors. The large solar mixing angle theta12 offers a way to probe otherwise inaccessible features of supernova physics. Finally, I note that in low-scale models of neutrino mass, one may probe all mixing angles, including the atmospheric theta23, at high energy accelerator experiments such as the LHC or NLC. A neat example is supersymmetry with bilinear breaking of R parity, where the LSP decay branching ratios are directly correlated to the neutrino mixing angles. I also discuss non-oscillation solutions to the solar neutrino problem in terms of spin-flavor precession and non-standard neutrino interactions, which will be crucially tested at KamLAND.
In this talk, we will discuss phenomenology of new physics associated with neutrinos, in particular, non-standard neutrino interactions, non-unitarity of the lepton mixing matrix, and secret neutrino interactions mediated by a light field.
After a brief history of two known types of neutrino mixing and oscillations, including neutrino spin and spin-flavour oscillations in the transversal magnetic field, we perform systematic study of a new phenomenon of neutrino spin and spin-flavour oscillations engendered by the transversal matter currents on the bases of the developed quantum treatment of the phenomenon. Possibilities for the resonance amplification of these new types of oscillations by the longitudinal matter currents and longitudinal magnetic fields are analyzed. Neutrino spin-flavour oscillations engendered by the transver…
We search for scalar and tensor non-standard interactions using (anti)-electron neutrino disappearance in oscillation data. We found a slight preference for non-zero CP violation, coming from both tensor and scalar interactions. The preference for CP violation is lead by Daya Bay low-energy data with a significance that reaches $\sim1.7σ$ in the global analysis (and $\sim2.1σ$ when considering only medium baseline reactors data) compared to the standard neutrino oscillation scenario.
Many scenarios of new physics predict the existence of neutrino Non-Standard Interactions, new vector contact interactions between neutrinos and first generation fermions beyond the Standard Model. We obtain model-independent constraints on the Standard Model Effective Field Theory at high energies from bounds on neutrino non-standard interactions derived at low energies. Our analysis explores a large set of new physics scenarios and includes full one-loop running effects below and above the electroweak scale. Our results show that neutrino non-standard interactions already push the scale of n…
Probing non-standard neutrino-electron interactions with solar and reactor neutrinos
标准电弱模型的大多数中微子质量扩展都包含非标准相互作用，在低能极限下，这些非标准相互作用可以用有效的四费米子算符$ν_αν_β\bar f f $来参数化。典型的亚弱强度，$ε_{αβ} G_F$，这些特征在于无量纲耦合参数，$ε_{αβ}$，这可能是相当大的一个广泛的类别的计划。在这里，我们专注于非通用（NU）的味道保存耦合（$α= β$）与电子（$f = e$），并分析其对太阳中微子的现象学的影响。我们始终考虑到他们的影响，在传播的水平，他们修改标准的MSW行为，并在检测水平，他们影响的电子上的中微子弹性散射的截面。我们发现的限制是可比的其他现有的模型独立的约束。
Charged currents are probed in low-energy precision $β$-decay experiments and at high-energy colliders, both of which aim to measure or constrain signals of beyond-the-Standard-Model physics. In light of future $β$-decay and LHC measurements that will further explore these non-standard interactions, we investigate what neutrinoless double-$β$ decay ($0νββ$) experiments can tell us if a nonzero signal were to be found. Using a recently developed effective-field-theory framework, we consider the effects that interactions with right-handed neutrinos have on $0νββ$ and discuss the range of neutrin…
