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Related papers: Dineutrino modes probing lepton flavor violation

200 papers

In recent years, experiments revealed intriguing hints for new physics (NP) in semi-leptonic $B$ decays. Both in charged current processes, involving $b \to c \tau \nu$ transitions, and in the neutral currents $b\to s\ell^+\ell^-$, a…

High Energy Physics - Phenomenology · Physics 2020-10-19 Andreas Crivellin , Dario Müller , Francesco Saturnino

We investigate the viability of extending the Standard Model with $S_1$ and $S_3$ scalar leptoquarks when the flavour structure is parametrized in terms of Froggatt-Nielsen charges. In contrast to a similar analysis with a vector…

High Energy Physics - Phenomenology · Physics 2021-03-17 Marzia Bordone , Oscar Cata , Thorsten Feldmann , Rusa Mandal

We present an overview of searches fo violation of lepton flavor universality with focus on low energy precision probes using pions, kaons, tau leptons, and nuclear beta decays. The current experimental results are reviewed, the theoretical…

High Energy Physics - Phenomenology · Physics 2022-10-12 Douglas Bryman , Vincenzo Cirigliano , Andreas Crivellin , Gianluca Inguglia

We study the implications of the global $U(1)_R$ symmetry present in minimal lepton flavor violating implementations of the seesaw mechanism for neutrino masses. Our discussion is done in the context of explicit minimal type-I seesaw…

High Energy Physics - Phenomenology · Physics 2012-09-14 Audrey Degée

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 $\mu\to e\gamma$ in generic leptoquark models.…

High Energy Physics - Phenomenology · Physics 2018-02-07 Andreas Crivellin , Dario Mueller , Adrian Signer , Yannick Ulrich

In the framework of the minimal ${SU}(3)_C\otimes {SU}(3)_L \otimes {U}(1)_N$ model, the lepton-flavour-violating decay $\pi^+ \ra \mu^- \nu_\mu e^+ e^+ $ is calculated without directly invoking lepton mixing. The branching ratio for this…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hoang Ngoc Long

We propose a generation dependent lepton/baryon gauge symmetry, $U(1)_{B_3 - x_\mu L_\mu - x_\tau L_\tau} \equiv U(1)_X$ (with $x_\mu + x_\tau =1$ for anomaly cancellation), as a possible solution for the $b \rightarrow s \mu^+ \mu^-$…

High Energy Physics - Phenomenology · Physics 2019-05-28 P. Ko , Takaaki Nomura , Chaehyun Yu

Rare charm decays offer the unique possibility to explore flavour-changing neutral-currents in the up-sector within the Standard Model and beyond. Due to the lack of effective methods to reliably describe its low energy dynamics, rare charm…

High Energy Physics - Phenomenology · Physics 2021-04-12 Hector Gisbert , Marcel Golz , Dominik Stefan Mitzel

There are discrepancies between the experimental results and the Standard Model predictions, in the lepton flavor universality of the semileptonic $B$ decays: $B \to D^{(*)} \ell \nu$. As the new physics interpretations, new charged vector…

High Energy Physics - Phenomenology · Physics 2019-04-17 Syuhei Iguro , Yuji Omura , Michihisa Takeuchi

Model-independent description of nonleptonic decays of charmed mesons is a challenging task due to large nonperturbative effects of strong interactions on the transition amplitudes. We discuss the equivalence of two different…

High Energy Physics - Phenomenology · Physics 2021-10-07 Bhubanjyoti Bhattacharya , Alakabha Datta , Alexey A. Petrov , John Waite

We propose improved Lepton Flavor Universality (LFU) ratios in semileptonic $P\to V \ell \bar{\nu}$ decays, when comparing $\mu$ and $\tau$ modes, that minimize the theoretical form-factor uncertainties. These optimized ratios are obtained…

High Energy Physics - Phenomenology · Physics 2020-12-30 Gino Isidori , Olcyr Sumensari

The flavor structure of quarks and leptons is not yet fully understood, but it hints a more fundamental theory of non-universal generations. We therefore propose a simple extension of the Standard Model by flipping (i.e., enlarging) the…

High Energy Physics - Phenomenology · Physics 2024-07-09 Duong Van Loi , Phung Van Dong , N. T. Duy , Nguyen Huy Thao

We construct a novel flavor-dependent gauged lepton number $U(1)_\ell$ model for the hierarchical charged lepton masses and the observed $(g-2)_{e,\mu}$. Only tau participates in the tree-level Standard Model ( SM ) Yukawa interaction. At…

High Energy Physics - Phenomenology · Physics 2022-12-22 We-Fu Chang

We review results on rare and forbidden decays of D^0, D^+, and D^+_s mesons from experiments at FNAL. The decay modes studied have two leptons in the final state and, if observed, would constitute evidence for flavor-changing…

High Energy Physics - Experiment · Physics 2007-05-23 A. J. Schwartz

The gauge interactions of any supersymmetric extension of the standard model involve new flavor mixing matrices. The assumptions involved in the construction of minimal supersymmetric models, both $SU(3) \times SU(2) \times U(1)$ and grand…

High Energy Physics - Phenomenology · Physics 2009-10-28 Nima Arkani-Hamed , Hsin-Chia Cheng , L. J. Hall

The charged lepton flavour violating (LFV) radiative decays, $\mu\to e+\gamma$, $\tau\to \mu+\gamma$ and $\tau\to e +\gamma$ are investigated in a class of supersymmetric $A_4$ models with three heavy right-handed (RH) Majorana neutrinos,…

High Energy Physics - Phenomenology · Physics 2014-11-20 C. Hagedorn , E. Molinaro , S. T. Petcov

U(1)-family symmetries have led to successful predictions of the fermion mass spectrum and the mixing angles of the hadronic sector. In the context of the supersymmetric unified theories, they further imply a non-trivial mass structure for…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mario E. Gomez

In the Standard Model, the three charged lepton are identical copies of each other, apart from mass differences. Experimental tests of this feature in decays of semileptonic b hadrons, such as $B\rightarrow D^* \tau\ nu$, are highly…

High Energy Physics - Experiment · Physics 2017-10-03 Benedetto Gianluca Siddi

We examine the parameter space region of the inverse seesaw model that is consistent with neutrino oscillation data. We focus on the correlation between the current limits from the search of the $\mu\to e\gamma$ lepton flavor violating…

High Energy Physics - Phenomenology · Physics 2023-08-28 J. C. Garnica , G. Hernández-Tomé , E. Peinado

One of the possible ways to explain the observed flavour structure of fundamental particles is to include flavor symmetries in the theories. In this work, we investigate the rare charged lepton flavour violating (cLFV) decay process ($\mu…

High Energy Physics - Phenomenology · Physics 2023-01-30 Maibam Ricky Devi , Kalpana Bora