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Electric dipole moments (EDMs) of charged leptons arise from a new source of CP violation in the lepton sector. In this paper, we calculate the EDMs of the charged leptons in the minimal scotogenic model with two singlet fermions, and the…

High Energy Physics - Phenomenology · Physics 2021-04-15 Motoko Fujiwara , Junji Hisano , Chihiro Kanai , Takashi Toma

In this work we study the short-range contributions that induce effective lepton number violating (LNV) interactions. We obtain a full set of constraints on the effective short-range couplings from a large variety of low-energy $|\Delta L|=…

High Energy Physics - Phenomenology · Physics 2016-11-07 Nestor Quintero

A phenomenological analysis of the three-family model based on the local gauge group $SU(3)_c\otimes SU(3)_L\otimes U(1)_X$ with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry…

High Energy Physics - Phenomenology · Physics 2008-11-26 Juan C. Salazar , William A. Ponce , Diego A. Gutiérrez

In previous studies we found that models with flavor-universal suppression of the neutrino-gauge couplings are compatible with NuTeV and Z-pole data. In this paper we expand our analysis to obtain constraints on flavor-dependent coupling…

High Energy Physics - Phenomenology · Physics 2007-05-23 Will Loinaz , Naotoshi Okamura , Saifuddin Rayyan , Tatsu Takeuchi , L. C. R. Wijewardhana

The Standard Model stands as the first established, complete (gravity aside), fundamental theory of nature. In the other hand, it is unable to account for some universal observations -- besides possessing a number of undesirable…

High Energy Physics - Phenomenology · Physics 2024-06-17 Mario W. Barela

We study anomalous magnetic moments and flavor violating processes of $e$, $\mu$ and $\tau$ leptons. We use a data driven approach to investigate the implications of the present data on the parameters of a class of models, which has spin-0…

High Energy Physics - Phenomenology · Physics 2020-10-07 Chun-Khiang Chua

We study the phenomenological constraints and consequences in the flavor sector, of introducing a new fourth generation $\mathcal{Z}_{2}$ odd vector-like lepton doublet along with a Standard Model (SM) singlet scalar and an $SU(2)_{L}$…

High Energy Physics - Phenomenology · Physics 2018-06-05 Lobsang Dhargyal , Santosh Kumar Rai

A plethora of ultraviolet completions of the Standard Model have extra U(1) gauge symmetries. In general, the associated massive $Z^\prime$ gauge boson can mediate flavor-changing neutral current processes at tree level. We consider a…

High Energy Physics - Phenomenology · Physics 2017-05-24 Patrick Foldenauer , Joerg Jaeckel

We examine the lepton flavor-changing processes in R-parity violating MSSM. First, we update the constraints on the relevant R-violating couplings by using the latest data on the rare decays l_i->l_j \gamma. We find that the updated…

High Energy Physics - Phenomenology · Physics 2010-01-08 Junjie Cao , Lei Wu , Jin Min Yang

Recent results from the intensity frontier indicate the tantalizing possibility of violation in lepton flavour universality. In light of this we revisit the minimal phenomenological $Z'$ model taking in account both vectorial and…

High Energy Physics - Phenomenology · Physics 2023-01-03 Tirtha Sankar Ray , Avirup Shaw

We study $b \to s \ell_1^+ \ell_2^-$ transitions, both for the lepton flavour conserving $\ell_1=\ell_2$ and violating case $\ell_1 \neq \ell_2$, in a minimal extension of the Standard Model proposed in [1]. In this framework, the Standard…

High Energy Physics - Phenomenology · Physics 2026-01-23 Pietro Colangelo , Fulvia De Fazio , Davide Milillo

There are theoretical and phenomenological motivations that there may exist additional heavy Z' bosons with family non-universal couplings. Flavor mixing in the quark and lepton sectors will then lead to flavor changing couplings of the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Paul Langacker , Michael Plumacher

The tension among measurements of $V_{us}$ from different channels, the so-called Cabibbo Angle Anomaly, can be interpreted as a signal of lepton flavor universality (LFU) violation in the $W$ boson couplings. We investigate this issue in…

High Energy Physics - Phenomenology · Physics 2021-09-22 Ashutosh Kumar Alok , Amol Dighe , Shireen Gangal , Jacky Kumar

The weak dipole moments of leptons and quarks, \ie those related to their $Z$--coupling, are reviewed. Standard Model predictions and experimental results may result in a stringent test for both their pointlike structure and also for the…

High Energy Physics - Phenomenology · Physics 2016-08-15 J. Bernabéu , G. A. González-Sprinberg , J. Vidal

The existence of anomalous electric($\tilde \kappa$) and/or magnetic($\kappa$) dipole moment couplings between the heavy flavor fermions ($c,b,\tau$) and the $Z$ boson can cause significant shifts in the values of several electroweak…

High Energy Physics - Phenomenology · Physics 2009-10-28 Thomas G. Rizzo

We consider an $SU(3)_L\otimes U(1)_N$ model for the electroweak interactions which includes extra charged leptons which do not mix with the known leptons. These new leptons couple to $Z^0$ only through vector currents. We consider…

High Energy Physics - Phenomenology · Physics 2009-10-22 V. Pleitez , M. D. Tonasse

We consider an abelian extension of the Standard Model (SM) comprising a new gauge group $U(1)^\prime$, with the neutral gauge boson $Z^\prime$ having flavour violating couplings to quarks and leptons. The fermion content is the same as in…

High Energy Physics - Phenomenology · Physics 2025-11-27 Pietro Colangelo , Fulvia De Fazio , Davide Milillo

We study lepton flavor violating (LFV) $B$ decays in a general two Higgs doublet model with sub-TeV exotic scalars. Two different parameter spaces are explored: one dominated by extra top Yukawa coupling $\rho_{tt}$, the other by LFV…

High Energy Physics - Phenomenology · Physics 2023-05-24 Wei-Shu Hou , Girish Kumar , Sven Teunissen

We employ data from precision electroweak tests and collider searches to derive constraints on the possibility that weak-singlet fermions mix with the ordinary Standard Model fermions. Our findings are presented within the context of a…

High Energy Physics - Phenomenology · Physics 2009-10-31 Marko B. Popovic , Elizabeth H. Simmons

In a simple extension of the standard model (SM), a pair of vector like lepton doublets ($L_1$ and $L_2$) and a $SU(2)_L$ scalar doublet ($\eta$) have been introduced to help in accommodating the discrepancy in determination of the…

High Energy Physics - Phenomenology · Physics 2022-08-29 Bibhabasu De , Debottam Das , Manimala Mitra , Nirakar Sahoo