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Related papers: Fourth Generation Leptons and Muon $g-2$

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We study the lepton flavor violation (LFV), the leptonic magnetic moments $(g-2)_{\mu,\,e} $ and the electric dipole moment (EDM) of the electron in the Standard-Model Effective Field Theory with the $\Gamma_N$ modular flavor symmetry. We…

High Energy Physics - Phenomenology · Physics 2022-08-24 Tatsuo Kobayashi , Hajime Otsuka , Morimitsu Tanimoto , Kei Yamamoto

Based on the bound state description of the muon and general relativistic covariant quantum field theory, we illustrate with a simple composite model that the observed deviation of (g-2)_\mu can be a demonstration of the substructure of the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yuan-Ben Dai , Chao-Shang Huang , Ailin Zhang

The electric dipole moment of the muon ($d_\mu$) is evaluated in a two Higgs doublet model with a softly broken discrete symmetry. The leading contributions from both one loop and two loop diagrams are considered. For $\tan\beta \equiv…

High Energy Physics - Phenomenology · Physics 2009-09-15 Vernon Barger , Ashok Das , Chung Kao

We construct a $Z_8$ model for leptons where all Yukawa couplings are of order unity, but known lepton masses are generated radiatively, {\it order by order}. The seed is provided by fourth generation leptons $E$ and $N$, which receive…

High Energy Physics - Phenomenology · Physics 2009-09-25 Gwo-Guang Wong , Wei-Shu Hou

In this study, we investigate the anomalous magnetic moment of the muon $(g_\mu-2)$ as reported by Fermilab (FNAL), along with the recent measurement of the $W$-boson mass by the CDF-II collaboration. Both findings show significant…

High Energy Physics - Phenomenology · Physics 2024-01-05 Rachid Benbrik , Mohammed Boukidi , Bouzid Manaut

This paper reports the tenth-order QED contribution to lepton g-2 from diagrams of three gauge-invariant sets VI(d), VI(g), and VI(h), which are obtained by including various fourth-order radiative corrections to the sixth-order g-2…

High Energy Physics - Phenomenology · Physics 2010-12-24 T. Aoyama , M. Hayakawa , T. Kinoshita , M. Nio

If new sequential leptons $E^\pm$ and $N^0$ exist, the LEP bound implies $m_E$, $m_N > M_Z/2$. The heaviness of the neutral lepton breaks away from the pattern of the first three generations. The minimal model is to have 4 left-handed…

High Energy Physics - Phenomenology · Physics 2009-10-22 Wei-Shu Hou , Gwo-Guang Wong

We study the lepton sector of composite Higgs models with partial compositeness. The standard anarchic scenario is in conflict with the absence of observable charged lepton flavor violation. This tension can be completely solved in MFV…

High Energy Physics - Phenomenology · Physics 2015-06-16 Michele Redi

We have studied the leptonic EDM and the LFV decays relating with the recent data of anomalous magnetic moment of muon, $(g-2)_{\mu}$ in the leptonic dipole operator. We have adopted the successful $\Gamma_2$ modular invariant model by…

High Energy Physics - Phenomenology · Physics 2024-12-18 Takaaki Nomura , Morimitsu Tanimoto , Xing-Yu Wang

The two--loop mechanism of Bjorken and Weinberg is used to constrain flavor changing neutral Higgs bosons. We calculate the complete set of two--loop diagrams for the rare decay $\mu \rightarrow e + \gamma$ induced by such neutral Higgs…

High Energy Physics - Phenomenology · Physics 2009-09-01 D. Chang , W. -S Hou , W. -Y. Keung

Updating various theoretical and experimental constraints on the four different types of two-Higgs-doublet models (2HDMs), we find that only the ``lepton-specific" (or ``type X") 2HDM can explain the present muon g$-$2 anomaly in the…

High Energy Physics - Phenomenology · Physics 2016-09-21 Eung Jin Chun

The one loop contribution to the lepton flavor violating decay $h^0\rightarrow \mu\tau$ of the SM-like neutral Higgs (LFVHD) in the 3-3-1 model with neutral lepton is calculated using the unitary gauge. We have checked in detail that the…

High Energy Physics - Phenomenology · Physics 2016-04-07 L. T. Hue , H. N. Long , T. T. Thuc , T. Phong Nguyen

This paper reports the tenth-order contributions to the g-2 of the electron a_e and those of the muon a_mu from the gauge-invariant Set II(c), which consists of 36 Feynman diagrams, and Set II(d), which consists of 180 Feynman diagrams.…

High Energy Physics - Phenomenology · Physics 2015-03-17 T. Aoyama , M. Hayakawa , T. Kinoshita , M. Nio

Minimal extensions of the Standard Model that are motivated by grand unified theories or superstring models with an E_6 symmetry can naturally predict heavy neutrinos of Dirac or Majorana nature. Such heavy neutral leptons violate the de-…

High Energy Physics - Phenomenology · Physics 2011-04-15 Apostolos Pilaftsis

The deviation of the measured value of the muon anomalous magnetic moment from the standard model prediction can be completely explained by mixing of the muon with extra vectorlike leptons, L and E, near the electroweak scale. This mixing…

High Energy Physics - Phenomenology · Physics 2013-08-09 Radovan Dermisek , Aditi Raval

One simple way to lower the scale of the seesaw mechanism that generates neutrino masses is to attribute part of their smallness to a suppressed vacuum expectation value of a second Higgs doublet as in the neutrinophilic 2HDM or in the type…

High Energy Physics - Phenomenology · Physics 2023-08-29 A. L. Cherchiglia , G. De Conto , C. C. Nishi

We studied an extension of the standard model with a fourth generation of fermions to explain the discrepancy in the muon $(g-2)$ and explain the positron excess seen in the AMS-02 experiment. We introduce a gauged $SU(2)_{HV}$ horizontal…

High Energy Physics - Phenomenology · Physics 2015-06-19 Gaurav Tomar , Subhendra Mohanty

We investigate the possibility of explanation for the muon anomalous magnetic moment $g_\mu-2$ in a left-right model with an inverse seesaw mechanism. We emphasize that the observed deviation from the Standard Model predictions can be…

High Energy Physics - Phenomenology · Physics 2023-03-31 M. Ashry , K. Ezzat , S. Khalil

In extended Higgs models, a discrete symmetry is needed in the quark sector to avoid tree-level flavor-changing neutral currents. However, this is not necessary the case in the lepton sector. We consider a model in which one Higgs couples…

High Energy Physics - Phenomenology · Physics 2023-05-17 B. L. Gonçalves , Matthew Knauss , Marc Sher

Muon lepton flavor processes are reviewed in connection with search for physics beyond the standard model. Several methods to distinguish different theoretical models are discussed for $\mu \to e \gamma$, $\mu \to 3 e$, and $\mu - e$…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yasuhiro Okada