Some consequences in weak processes of three-generation mixing in the leptonic sector

Crucial developments in neutrino physics would be the determination of the mass hierarchy (MH) and measurement of the CP phase in the leptonic sector. The patterns of the transition probabilities [Formula: see text] and [Formula: see text] are sensitive to these oscillation parameters. An asymmetry parameter can be defined as the difference of these two probabilities normalized to their sum. The profile of the asymmetry parameter gives a clear signal of the mass ordering as it is found to be positive for inverted hierarchy and negative for normal hierarchy. The asymmetry parameter is also sensitive to the CP phase. We consider the effects of nonstandard neutrino interactions (NSI) on the determination of the mass hierarchy. Since we assume the largest new physics effects involve the [Formula: see text] sector only, we ignore NSI in production and study the NSI effects in detection as well as along propagation. We find that the NSI effects can significantly modify the prediction of the asymmetry parameter though the MH can still be resolved.

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POSSIBILITY OF OBSERVING LEPTONIC CP VIOLATION WITH PERTURBED DEMOCRATIC MIXING PATTERNS

Modern Physics Letters A ◽

10.1142/s0217732312501751 ◽

2012 ◽

Vol 27 (31) ◽

pp. 1250175 ◽

Cited By ~ 3

Author(s):

K. N. DEEPTHI ◽

R. MOHANTA

Keyword(s):

Cp Violation ◽

Precise Measurement ◽

Daya Bay ◽

Leptonic Sector ◽

Mixing Matrix ◽

Mixing Patterns

The Daya Bay oscillation has recently reported the precise measurement of θ13≃8.8°±0.8° or θ13 ≠0 at 5.2 σ level. The observed nonzero θ13 can be accommodated by some general modifications to the democratic mixing matrix. Using such matrices we study the possibility of observing nonzero CP violation in the leptonic sector.

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CP PHASES IN THE LEPTONIC SECTOR OF LRSUSY AND LEPTOGENESIS

International Journal of Modern Physics A ◽

10.1142/s0217751x0402261x ◽

2004 ◽

Vol 19 (31) ◽

pp. 5377-5384

Author(s):

M. FRANK

Keyword(s):

Light Neutrino ◽

Supersymmetric Model ◽

Neutrino Mixing ◽

Lepton Flavor ◽

Leptonic Sector ◽

Minimal Supersymmetric Model ◽

Majorana Phases

We analyze the effects of the current neutrino data on thermal leptogenesis and lepton flavor violating and conserving processes in a fully left-right extension of the minimal supersymmetric model. The model has several phases from both the heavy and light neutrino sectors: two CKM-type phases, and four Majorana phases, which give new contributions to CP-violating parameters and leptogenesis. We study observable effects of these phases in most general neutrino mixing scenarios, with either hierarchical, inverse hierarchical or quasi-degenerate light and heavy neutrinos. The CP violating phases in both the heavy and light neutrino sectors of the left-right supersymmetric model have unique features which may distinguish the model from other supersymmetric scenarios.

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Testing the Equivalence Principle Using g-2 Experiments

Modern Physics Letters A ◽

10.1142/s0217732397001230 ◽

1997 ◽

Vol 12 (17) ◽

pp. 1209-1224 ◽

Cited By ~ 3

Author(s):

R. B. Mann

Keyword(s):

Equivalence Principle ◽

Magnetic Moments ◽

Precession Frequency ◽

Leptonic Sector

I discuss the utility of anomalous magnetic moments of elementary leptons as a test of the Einstein Equivalence Principle (EEP). Violations of the EEP in the leptonic sector give rise to novel effects which are manifest in qualitatively different changes in the anomalous precession frequency. The Brookhaven muon-(g-2) experiment E821 can search for such effects directly, offering us a new empirical window into the validity of the EEP.

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Implications of the Muon g-2 result on the flavour structure of the lepton mass matrix

The European Physical Journal C ◽

10.1140/epjc/s10052-021-09741-1 ◽

2021 ◽

Vol 81 (10) ◽

Author(s):

Lorenzo Calibbi ◽

M. L. López-Ibáñez ◽

Aurora Melis ◽

Oscar Vives

Keyword(s):

Mass Matrix ◽

New Physics ◽

Flavor Symmetry ◽

Moment Matrix ◽

Leptonic Sector ◽

Mass Matrices ◽

The Standard Model ◽

Model Predictions ◽

Low Energies ◽

Lepton Flavour

AbstractThe confirmation of the discrepancy with the Standard Model predictions in the anomalous magnetic moment by the Muon g-2 experiment at Fermilab points to a low scale of new physics. Flavour symmetries broken at low energies can account for this discrepancy but these models are much more restricted, as they would also generate off-diagonal entries in the dipole moment matrix. Therefore, if we assume that the observed discrepancy in the muon $$g-2$$ g - 2 is explained by the contributions of a low-energy flavor symmetry, lepton flavour violating processes can constrain the structure of the lepton mass matrices and therefore the flavour symmetries themselves predicting these structures. We apply these ideas to several discrete flavour symmetries popular in the leptonic sector, such as $$\Delta (27)$$ Δ ( 27 ) , $$A_4$$ A 4 , and $$A_5 < imes \mathrm{CP}$$ A 5 ⋉ CP .

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The leptonic sector

Electroweak Theory ◽

10.1017/cbo9780511611049.009 ◽

2009 ◽

pp. 64-77

Author(s):

E. A. Paschos

Keyword(s):

Leptonic Sector

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Phenomenology of the partially aligned 2HDM with leptonic meson decays

International Journal of Modern Physics A ◽

10.1142/s0217751x19501987 ◽

2019 ◽

Vol 34 (30) ◽

pp. 1950198 ◽

Cited By ~ 1

Author(s):

A. Carrillo-Monteverde ◽

S. Gómez-Ávila ◽

R. Gómez-Rosas ◽

L. López-Lozano ◽

A. Rosado

Keyword(s):

Higgs Doublet ◽

New Physics ◽

Tree Level ◽

Flavor Symmetry ◽

Leptonic Decays ◽

Quark Sector ◽

Leptonic Sector ◽

Doublet Model ◽

Free Parameters ◽

Two Higgs Doublet Model

In this paper we present a phenomenological analysis of the Partially Aligned Two Higgs Doublet Model (PA-2HDM) by using leptonic decays of mesons and [Formula: see text]–[Formula: see text] mixing. We focus our attention in a scenario where the leading contribution to FCNC is given by the tree-level interaction with the light pseudoscalar [Formula: see text] ([Formula: see text] GeV). We show how an underlying flavor symmetry controls FCNC in the quark and lepton couplings with the pseudoscalar, without alignment between Yukawa matrices. Upper bounds on the free parameters are calculated in the context of the leptonic decays [Formula: see text] and [Formula: see text] and [Formula: see text] mixing. Also, our assumptions imply that bounds on New Physics contribution in the quark sector coming from [Formula: see text] mixing impose an upper bound on the parameters for the leptonic sector. Finally we give predictions of branching ratios for leptonic decay of mesons with FCNC and LFV.

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