What is Leading Order for LFV in SMEFT?

Abstract

Upcoming searches for lepton flavour change (LFV) aim to probe New Physics(NP) scales up to $\sim 10^4$ TeV, implying that they will be sensitive to NP at lower scales that is suppressed by loops or small couplings. We suppose that the NP responsable for LFV is beyond the reach of the LHC and can be parametrised in Effective Field Theory, introduce a small power-counting parameter à la Cabibbo-Wolfenstein, and assess whether the existing dimension six operator basis and one-loop RGEs provide a good approximation for LFV. We find that mu to e flavour-changing observables can be sensitive to a few dozen dimension eight operators, and to some effects of two-loop anomalous dimensions, for NP scales below 20-100 TeV. We also explore the effect of some simplifying assumptions in the one-loop RGEs, such as neglecting flavour-changing effects.

arXiv comment12 pages+2 appendices

References in corpus (36)

• Dimension-Six Terms in the Standard Model Lagrangian
• Minimal Flavour Violation: an effective field theory approach
• 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
• Refinements in electroweak contributions to the muon anomalous magnetic moment
• Search for Lepton Flavor Violating Tau Decays into Three Leptons with 719 Million Produced Tau+Tau- Pairs
• The design of the MEG II experiment
• Complete Electroweak Chiral Lagrangian with a Light Higgs at NLO
• Weak Hamiltonian, CP Violation and Rare Decays
• 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
• Complete Set of Dimension-8 Operators in the Standard Model Effective Field Theory
• Electromagnetic Logarithms in B -> X_s l+ l-
• Search for the decay $B_s^0\to {\overline{D}}^0{f}_0(980)$
• Low-energy effective field theory below the electroweak scale: matching at one loop
• Evanescent Operators, Scheme Dependences and Double Insertions
• Evidence for Higgs boson decay to a pair of muons
• Higgs-dependent Yukawa couplings
• Renormalisation-group improved analysis of $\mu \to e$ processes in a systematic effective-field-theory approach
• A search for the dimuon decay of the Standard Model Higgs boson with the ATLAS detector
• Leading Order QCD Corrections to $b\to s\gamma$ and $b\to sg$ Decays in Three Regularization Schemes
• Research Proposal for an Experiment to Search for the Decay μ -> eee
• Search for lepton-flavour-violating decays of the Higgs and $Z$ bosons with the ATLAS detector
• 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
• Constraints on two-lepton, two quark operators
• Effective Theory of a Dynamically Broken Electroweak Standard Model at NLO
• Effective Theory Approach to New Physics with Flavour: General Framework and a Leptoquark Example
• Completeness and Complementarity for $\mu \to e\gamma$, $\mu \to 3e$ and $\mu \to e$ conversion
• Mu to e gamma and matching at mW
• Fingerprints of heavy scales in electroweak effective Lagrangians
• Low-energy signals of strongly-coupled electroweak symmetry-breaking scenarios
• Probing $\mu e\gamma \gamma$ contact interactions with $\mu \to e$ conversion
• Constraints on 2l2q operators from $\mu -e$ flavour-changing meson decays
• Charged lepton flavour change and Non-Standard neutrino Interactions
• Using dipole processes to constrain the flavour of four-fermion effective interactions

Cited by in corpus (10)

• Towards the renormalisation of the Standard Model effective field theory to dimension eight: Bosonic interactions I
• Introduction to Charged Lepton Flavour Violation
• Constraints on anomalous dimensions from the positivity of the S-matrix
• Reach and complementarity of $\mu \to e$ searches
• Renormalisation of SMEFT bosonic interactions up to dimension eight by LNV operators
• Gearing up for the next generation of LFV experiments, via on-shell methods
• Dimension-8 SMEFT Matching Conditions for the Low-Energy Effective Field Theory
• Z lepton flavour violation as a probe for new physics at future $e^{+}{e}^{-}$ colliders
• Two-to-two processes at an electron-muon collider
• A Green's basis for the bosonic SMEFT to dimension 8