Introduction to Charged Lepton Flavour Violation

Abstract

Neutrino masses provide evidence of lepton flavour violation, but no violation in the interactions among the charged leptons has been observed yet. Many models of Physics Beyond the Standard Model (BSM) predict Charged Lepton Flavour Violation (CLFV) in a wide spectrum of processes with rates in reach of upcoming experiments. The experimental searches that provide the current best limits on the CLFV searches are reviewed, with a particular emphasis on the muon-based experiments that give the most stringent constraints on BSM parameter space. The next generation of muon-based experiments (MEG-II, Mu2e, COMET, Mu3e) aim to reach improvements by many orders of magnitude w.r.t. the current best limits, thanks to several technological advancements. We review popular heavy BSM theories, and we present the calculations of the predicted CLFV branching ratios, focusing on the more sensitive $\mu \to e$ sector.

arXiv commentSeveral typos corrected. Improved appendix

References in corpus (115)

• Evidence for oscillation of atmospheric neutrinos
• Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory
• First Results from KamLAND: Evidence for Reactor Anti-Neutrino Disappearance
• Theory and phenomenology of two-Higgs-doublet models
• Dimension-Six Terms in the Standard Model Lagrangian
• A Supersymmetry Primer
• Verifiable Radiative Seesaw Mechanism of Neutrino Mass and Dark Matter
• Oscillating neutrinos and mu --> e, gamma
• R-parity violating supersymmetry
• The CP-conserving two-Higgs-doublet model: the approach to the decoupling limit
• Renormalization Group Evolution of the Standard Model Dimension Six Operators III: Gauge Coupling Dependence and Phenomenology
• Renormalization Group Evolution of the Standard Model Dimension Six Operators II: Yukawa Dependence
• Muon Decay and Physics Beyond the Standard Model
• Lepton-Flavor Violation via Right-Handed Neutrino Yukawa Couplings in Supersymmetric Standard Model
• Renormalization Group Evolution of the Standard Model Dimension Six Operators I: Formalism and lambda Dependence
• 2020 Global reassessment of the neutrino oscillation picture
• New solar opacities, abundances, helioseismology, and neutrino fluxes
• Searches for Lepton Flavor Violation in the Decays tau -> e gamma and tau -> mu gamma
• Measurement of the solar neutrino capture rate with gallium metal. III: Results for the 2002--2007 data-taking period
• The Belle II Physics Book
• New Limit for the Family-Number Non-conserving Decay mu+ to e+_gamma
• Search for Lepton Flavor Violating Tau Decays into Three Leptons with 719 Million Produced Tau+Tau- Pairs
• Measurement of the Solar Neutrino Capture Rate by the Russian-American Gallium Solar Neutrino Experiment During One Half of the 22-Year Cycle of Solar Activity
• Violations of lepton flavour and CP in supersymmetric unified theories
• Complete results for five years of GNO solar neutrino observations
• Detailed calculation of lepton flavor violating muon-electron conversion rate for various nuclei
• Basis-independent methods for the two-Higgs-doublet model
• From the trees to the forest: a review of radiative neutrino mass models
• Flavor Violating Higgs Decays
• Low energy effects of neutrino masses
• Solar and Atmospheric Neutrino Oscillations and Lepton Flavor Violation in Supersymmetric Models with Right-handed Neutrinos
• Unitarity of the Leptonic Mixing Matrix
• Measurement of Neutrino and Antineutrino Oscillations Using Beam and Atmospheric Data in MINOS
• High-precision determination of the pion-nucleon $\sigma$-term from Roy-Steiner equations
• First real time detection of Be7 solar neutrinos by Borexino
• Solar models with accretion. I. Application to the solar abundance problem
• The Scalar Strange Content of the Nucleon from Lattice QCD
• Dimension-8 Operators in the Standard Model Effective Field Theory
• Observation of the Higgs boson decay to a pair of tau leptons with the CMS detector
• Lepton Flavor Violation in the Scotogenic Model
• Extending the Standard Model Effective Field Theory with the Complete Set of Dimension-7 Operators
• Complete Set of Dimension-8 Operators in the Standard Model Effective Field Theory
• Cold Dark Matter, Radiative Neutrino Mass, mu to e gamma, and Neutrinoless Double Beta Decay
• Charged Lepton Flavor Violation: An Experimenter's Guide
• Do experiments suggest a hierarchy problem?
• Testing Supersymmetry with Lepton Flavor Violating tau and mu decays
• Measurements of branching fractions, rate asymmetries, and angular distributions in the rare decays B --> Kl+l- and B --> K*l+l-
• COMET Phase-I Technical Design Report
• Two--loop Contributions of Flavor Changing Neutral Higgs Boson to $\mu \to e\gamma$
• Renormalisation-group improved analysis of $\mu \to e$ processes in a systematic effective-field-theory approach
• Probing lepton flavour violation with Higgs boson decays H-> li+lj
• Probing the scotogenic model with lepton flavor violating processes
• Charged-Lepton-Flavour Violation in the Light of the Super-Kamiokande Data
• New Limit on Muon and Electron Lepton Number Violation from $K_L^0\to {\mu }^{\pm }{e}^{\mp }$ Decay
• Prospects for the Zee-Babu Model at the LHC and low energy experiments
• Low Energy Signatures of the TeV Scale See-Saw Mechanism
• Cross-section measurements of the Higgs boson decaying into a pair of tau-leptons in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Lepton Flavour Violation from SUSY--GUTs: Where do we stand for MEG, PRISM/PRIME and a Super Flavour factory
• Technical design of the phase I Mu3e experiment
• Reconciliation of CDM abundance and $\mu \to e\gamma$ in a radiative seesaw model
• The seesaw mechanism at arbitrary order: disentangling the small scale from the large scale
• Search for a scalar partner of the top quark in the jets plus missing transverse momentum final state at $\sqrt{s}$=13 TeV with the ATLAS detector
• Radiative seesaw: Warm dark matter, collider and lepton flavour violating signals
• New Constraints On Lepton Nonconserving R-parity Violating Couplings
• Lepton Flavour Violation and theta(13) in Minimal Resonant Leptogenesis
• Lepton flavor violation in Higgs boson decays under the rare tau decay results
• Spin-dependent $\mu \to e$ conversion
• Determining See-Saw Parameters from Weak Scale Measurements?
• The Zee-Babu Model revisited in the light of new data
• Experimental tests for the Babu-Zee two-loop model of Majorana neutrino masses
• Search for the lepton flavor violating decay $Z\to e\mu$ in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector
• Lepton Flavour Violation In Supersymmetric Models with Trilinear R-parity Violation
• Bounds on R-parity violating supersymmetric couplings from leptonic and semi-leptonic meson decays
• Search for Lepton Flavor Violating Decays of the Neutral Kaon
• Limits on tau Lepton-Flavor Violating Decays in three charged leptons
• A search for the decay modes B+/- to h+/- tau l
• Search for the lepton flavour violating decay ${\tau }^{-}\to {\mu }^{-}{\mu }^{+}{\mu }^{-}$
• Search for lepton-flavor violating decays of the Higgs boson in the $\mu \tau$ and e$\tau$ final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• Search for Lepton-Flavor-Violating tau Decays into a Lepton and a Vector Meson
• Search for Lepton Flavor Violating Decays ${\tau }^{\pm }\to {\ell }^{\pm }{\pi }^0,{\ell }^{\pm }\eta ,{\ell }^{\pm }{\eta }^{\prime }$
• New constraints on R-parity violation from μ-e conversion in nuclei
• Lepton Flavor Violation in the Two Higgs Doublet Model type III
• Higgs-Mediated e -> mu transitions in II Higgs doublet Model and Supersymmetry
• Search for the lepton-flavour-violating decays $B_s^0\to {\tau }^{\pm }{\mu }^{\mp }$ and $B^0\to {\tau }^{\pm }{\mu }^{\mp }$
• Constraints on $R$-parity violating interactions from $\mu \to e\gamma$
• MuSIC: delivering the world's most intense muon beam
• Complete One-loop Matching of the Type-I Seesaw Model onto the Standard Model Effective Field Theory
• Selecting mu -> e Conversion Targets to distinguish Lepton Flavour-Changing Operators
• Phenomenology of lepton flavor violation in 2HDM(III) from (g-2)_mu and leptonic decays
• An Improved upper limit on the decay K^+ -> pi^+ mu^+ e^-
• Spin-dependent $\mu \to e$ Conversion on Light Nuclei
• Searches for the decays B0 -> l+ tau- and B+ -> l+ nu (l=e,mu) using hadronic tag reconstruction
• New bounds on trilinear R-parity violation from lepton flavor violating observables
• Search for the lepton-flavour violating decays $B_s^0\to e^{\pm }{\mu }^{\mp }$ and $B^0\to e^{\pm }{\mu }^{\mp }$
• The Search for ${\mu }^{+}\to e^{+}\gamma$ with 10${}^{-14}$ Sensitivity: the Upgrade of the MEG Experiment
• Lepton Flavor Violating $\tau$ Decays in TeV Scale Type I See-Saw and Higgs Triplet Models
• What is Leading Order for LFV in SMEFT?
• Completeness and Complementarity for $\mu \to e\gamma$, $\mu \to 3e$ and $\mu \to e$ conversion
• Design and status of the Mu2e crystal calorimeter
• Constrained SUSY seesaws with a 125 GeV Higgs
• One-loop Matching of the Type-II Seesaw Model onto the Standard Model Effective Field Theory
• Lepton-flavour violation in hadronic tau decays and $\mu -\tau$ conversion in nuclei
• The MECO experiment: A search for lepton flavor violation in muonic atoms
• Probing $\mu e\gamma \gamma$ contact interactions with $\mu \to e$ conversion
• Search for the charged lepton flavor violating decay $J/\psi \to e\tau$
• On Power and Complementarity of the Experimental Constraints on Seesaw Models
• Bound muon decay spectrum in the leading logarithmic accuracy
• Status of Supersymmetric Seesaw in SO(10) models
• Search for the Lepton Flavor Violation Process $J/\psi \to e\mu$ at BESIII
• Performance of the large scale HV-CMOS pixel sensor MuPix8
• Constraints on 2l2q operators from $\mu -e$ flavour-changing meson decays
• Radiative decays of charged leptons as constraints of unitarity polygons for active-sterile neutrino mixing and CP violation
• Revisiting Flavor and CP Violation in Supersymmetric SU(5) with Right-Handed Neutrinos
• Bounds on R-parity violating SUSY Yukawa couplings from semileptonic decays of baryons
• Leptonic CP and Flavor Violations in SUSY GUT with Right-handed Neutrinos

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• Unveiling Neutrino Mysteries with $\Delta (27)$ Symmetry
• Study of neutrinoless double beta decay in the Standard Model extended with sterile neutrinos
• Leptons and other forces of Nature
• Search for the charged lepton flavor violating decay $\psi (3686)\to e^{\pm }{\mu }^{\mp }$
• Positron Transport System for Muonium-to-Antimuonium Conversion Experiment