Inspired by a new relation $θ_{13}^{\rm PMNS}={θ_C}/{\sqrt{2}}$ observed from the relatively large $θ_{13}^{\rm PMNS}$, we find that the combination of this relation with the quark-lepton complementarity and the self-complementarity results in correlations of the lepton mixing angles with the quark mixing angles. We find that the three mixing angles in the PMNS matrix are all related to the Wolfenstein parameter $λ$ in the quark mixing, so they are also correlated. Consequently, the PMNS matrix can be parameterized by $λ$, A, and a Dirac CP-violating phase $δ$. Such parametrizations for the PMNS matrix have the same explicitly hierarchical structure as the Wolfenstein parametrization for the CKM matrix in the quark mixing, and the bimaximal mixing pattern is deduced at the leading order. We also discuss implications of these phenomenological relations in parametrizations.
Starting with the Wolfenstein form for the leptonic mixing matrix we show that renormaliztion group evolution brings that to the observed large mixing at low energies.
A model-independent ansatz to describe lepton and quark mixing in a unified way is suggested based upon the Cabibbo angle. In our framework neutrinos mix in a "Bi-Large" fashion, while the charged leptons mix as the "down-type" quarks do. In addition to the standard Wolfenstein parameters (lambda, A) two other free parameters are needed to specify the physical lepton mixing matrix. Through this simple assumption one makes specific predictions for the atmospheric angle as well as leptonic CP violation in good agreement with current observations.
Two negative signs naturally appear in the $U_{μ1}$ and $U_{τ2}$ elements of the Tri-bimaximal (TBM) matrix for positive values of the mixing angles $θ_{12}$ and $θ_{23}$. Apart from this, in other TBM matrices negative signs are shifted to other elements in each case. They account for positive as well as negative values of $θ_{12}$ and $θ_{23}$. We discuss the sign ambiguity in the TBM matrix and find that the TBM matrices, in fact, can be divided into two groups under certain circumstances. Interestingly, this classification of TBM matrices is accompanied by two different $μ-τ$ symmetric mas…
In addition to the existing strong indications for lepton flavour university violation (LFUV) in low energy precision experiments, CMS recently released an analysis of non-resonant di-lepton pairs which could constitute the first sign of LFUV in high-energy LHC searches. In this article we show that the Cabibbo angle anomaly, an (apparent) violation of first row and column CKM unitarity with $\approx3\,σ$ significance, and the CMS result can be correlated and commonly explained in a model independent way by the operator $[Q_{\ell q}^{(3)}]_{1111} = (\bar{\ell}_1γ^μσ^I\ell_1)(\bar{q}_1γ_μσ^Iq_1…
Motivated by the measurements of $b\to s\ell^+\ell^-$ transitions, including $R(K)$ and $R(K^*)$, we examine lepton flavour (universality) violation in $B$ decays and its connections to $μ\to eγ$ in generic leptoquark models. Considering all 10 representations of scalar and vector leptoquarks under the Standard Model gauge group we compute the tree-level matching for semileptonic $b$-quark operators as well as their loop effects in $\ell\to\ell^\primeγ$. In our phenomenological analysis we correlate $R(K)$, $R(K^*)$ and the other $b\to sμ^+μ^-$ data to $μ\to eγ$ and $b\to sμe$ transitions for …
Correlating lepton flavor violating $b \to s$ and leptonic decay modes in a minimal abelian extension of the Standard Model
Istituto Nazionale di Fisica Nucleare, Sezione di Bari（意大利国家核物理研究所巴里分部）；Dipartimento Interuniversitario di Fisica “Michelangelo Merlin”, Università degli Studi di Bari “Aldo Moro”（巴里阿尔多·莫罗大学米开朗基罗·梅林跨学科物理学系）
Leptonic CP Violating Phase $ δ_{CP} $ in the light neutrino sector and leptogenesis via present matter antimatter asymmetry of the Universe entails each other. Probing CP violation in light neutrino oscillation is one of the challenging tasks today. The reactor mixing angle $ θ_{13} $ measured in reactor experiments, LBL, DUNE with high precision in neutrino experiments indicates towards the vast dimension of scope to detect $ δ_{CP} $. The correlation between leptonic Dirac CPV phase $ δ_{CP} $, reactor mixing angle $ θ_{13} $, lightest neutrino mass $ m_{1} $ and matter antimatter asymmetry…
We propose an $A_4$ extension of the Standard Model with a Lepton Quarticity symmetry correlating dark matter stability with the Dirac nature of neutrinos. The flavor symmetry predicts (i) a generalized bottom-tau mass relation involving all families, (ii) small neutrino masses are induced a la seesaw, (iii) CP must be significantly violated in neutrino oscillations, (iv) the atmospheric angle $θ_{23}$ lies in the second octant, and (v) only the normal neutrino mass ordering is realized.
Muon anomalous magnetic moment, lepton flavor violation, and flavor changing neutral current processes in SUSY GUT with right-handed neutrino
受大气和太阳中微子异常的大混合角解的启发，在SU（5）超对称大统一理论框架下分析了中微子味变中性流过程和轻子味破坏过程以及μ子反常磁矩.为了解释夸克和轻子的真实质量关系，我们考虑了GUT尺度以上的高维算子的影响。结果表明，超对称（SUSY）效应对$K^0-\bar{K}^0$混合CP破坏参数、$ε_K$、$μ\to e γ$分支比和μ子反常磁矩的贡献在很宽的参数空间范围内变大.我们还研究了这些量之间的相关性。在目前的实验范围内的$\text{B}(μ\to e γ)$，大超对称性的贡献是可能的，无论是在μ子异常磁矩或在$ε_K$。在前一种情况下，最近在BNL E821实验上测量的μ子异常磁矩的有利值可以被容纳。在后一种情况下，Kobayashi-Maskawa相的允许区域可能与标准模型（SM）中的预测不同，因此$B\to J/ψK_S$模式和$Δm_{B_s}$模式的CP不对称性的测量可以将这种情况与SM区分开来。当中微子参数与Mikheyev-Smirnov-Wolfenstein小混合角解一致时，$τ\to μγ$分支比可以接近当前实验上界，并且混合诱导的辐射B衰变CP不对称性可以增强.
We have studied neutrinoless double beta decay and charged lepton flavour violation in broken $μ-τ$ symmetric neutrino masses in a generic left-right symmetric model (LRSM). The leading order $μ-τ$ symmetric mass matrix originates from the type I (II) seesaw mechanism, whereas the perturbations to $μ-τ$ symmetry in order for generation of non-zero reactor mixing angle $θ_{13}$, as required by latest neutrino oscillation data, originates from the type II (I) seesaw mechanism. In our work, we considered four different realizations of $μ-τ$ symmetry, viz. Tribimaximal Mixing (TBM), Bimaximal Mixi…
The prediction of possible ordering of neutrino masses relies mostly on the model selected. Alienating the $μ-τ$ interchange symmetry from discrete flavour symmetry based models, turns the neutrino mass matrix less predictive. But this inspires one to seek the answer from other phenomenological frameworks. We need a proper parametrization of the neutrino mass matrices concerning individual hierarchies. In the present work, we attempt to study the six different cases of Quasi-degenerate (QDN) neutrino models. The related mass matrices, $m_{LL}^ν$ are parametrized with two free parameters ($α,η$…
Minimal Quark-Lepton Complementarity from a Rigid Deformation of Tri-Bimaximal Mixing
Centre for Research Impact and Outcome, Chitkara University（奇特卡拉大学研究影响与成果中心）；Department of Physics, Sharda School of Engineering & Science, Sharda University（沙达大学沙达工程与科学学院物理系）；Department of Physics, Rayat Bahra University（拉亚特巴哈大学物理系）
