Precision Tau Physics

Abstract

Precise measurements of the lepton properties provide stringent tests of the Standard Model and accurate determinations of its parameters. We overview the present status of tau physics, highlighting the most recent developments, and discuss the prospects for future improvements. The leptonic decays of the tau lepton probe the structure of the weak currents and the universality of their couplings to the W boson. The universality of the leptonic Z couplings has also been tested through leptonic Z decays. The hadronic tau decay modes constitute an ideal tool for studying low-energy effects of the strong interaction in very clean conditions. Accurate determinations of the QCD coupling and the Cabibbo mixing have been obtained with tau data. The large mass of the tau opens the possibility to study many kinematically-allowed exclusive decay modes and extract relevant dynamical information. Violations of flavour and CP conservation laws can also be searched for with tau decays. Related subjects such as muon decays, the electron and muon anomalous magnetic moments, neutrino mixing and B-meson decays into tau leptons are briefly covered. Being one the fermions most strongly coupled to the scalar sector, the tau lepton is playing now a very important role at the LHC as a tool to test the Higgs properties and search for new physics at higher scales.

66 pages, 16 figures. New Belle measurement of the tau lifetime included. Updated references. Matches version published in Progress in Particle and Nuclear Physics

References in corpus (55)

• Parton distributions for the LHC
• Observation of electron-antineutrino disappearance at Daya Bay
• Indication of Electron Neutrino Appearance from an Accelerator-produced Off-axis Muon Neutrino Beam
• Electroweak gauge boson production at hadron colliders through O(alpha_s^2)
• New determination of the fine structure constant and test of the quantum electrodynamics
• Global fit to three neutrino mixing: critical look at present precision
• Hadronic Z- and tau-Decays in Order alpha_s^4
• Flavour physics of leptons and dipole moments
• Implications of lepton flavor universality violations in B decays
• Muon g-2: Review of Theory and Experiment
• Improved predictions for g-2 of the muon and α_{\rm QED}(M_Z^2)
• Towards a consistent estimate of the chiral low-energy constants
• Update of the e^+e^-\toπ^+π^- cross section measured by SND detector in the energy region 400<\sqrt{s}<1000 MeV
• Evidence for B- -> tau- nu_tau-bar with a Hadronic Tagging Method Using the Full Data Sample of Belle
• alpha_s and the tau hadronic width: fixed-order, contour-improved and higher-order perturbation theory
• The Determination of alpha_s from Tau Decays Revisited
• Mass effects in muon and semileptonic b -> c decays
• Chiral perturbation theory
• Power corrections to alpha_s(M_τ),|V_{us}| and m_s
• pi/K -> e nu branching ratios to O(e^2 p^4) in Chiral Perturbation Theory
• The Hadronic Light-by-Light Contribution to the Muon Anomalous Magnetic Moment: Where do we stand?
• $\mu -e$ conversion in nuclei within the CMSSM seesaw: universality versus non-universality
• Lepton flavour violating semileptonic tau decays in constrained MSSM-seesaw scenarios
• A Rational Approach to Resonance Saturation in large-Nc QCD
• Impact of ${\theta }_{13}$ on Lepton Flavour Violating processes within SUSY Seesaw
• A note on isospin violation in Pl2(gamma) decays
• Tau anomalous magnetic moment form factor at Super B/Flavor factories
• What can be learned from the Belle spectrum for the decay tau- -> nu_tau K_S pi-
• K pi vector form factor constrained by tau ---> K pi nu_tau and K_l3 decays
• Analyticity constraints on the strangeness changing vector current and applications to $\tau \to K\pi {\nu }_{\tau }$, $\tau \to K\pi \pi {\nu }_{\tau }$
• Search for pair production of third-generation leptoquarks and top squarks in pp collisions at sqrt(s) = 7 TeV
• CP violation and Leptogenesis in models with Minimal Lepton Flavour Violation
• S-parameter and pseudo-Nambu-Goldstone boson mass from lattice QCD
• Form-factors and current correlators: chiral couplings L_10(mu) and C_87(mu) at NLO in 1/N(C)
• Predicting the tau strange branching ratios and implications for V_{us}
• The relation between the QED charge renormalized in MSbar and on-shell schemes at four loops, the QED on-shell beta-function at five loops and asymptotic contributions to the muon anomaly at five and six loops
• Lepton-Number Violating Decays of Heavy Mesons
• Search for the lepton-flavour violating decays $B_s^0\to e^{\pm }{\mu }^{\mp }$ and $B^0\to e^{\pm }{\mu }^{\mp }$
• ${\tau }^{-}\to K^{-}{\eta }^{(\prime )}{\nu }_{\tau }$ decays in Chiral Perturbation Theory with Resonances
• Tau spin correlations and the anomalous magnetic moment
• Improving the Hadron Physics of Non-Standard-Model Decays: Example Bounds on R-parity Violation
• CP violation and electric-dipole-moment at low energy $\tau$ production with polarized electrons
• W-propagator corrections to muon and tau leptonic decays
• Determination of QCD condensates from tau-decay data
• V_us From Hadronin Tau Decays
• Lepton flavor violation in the Simplest Little Higgs model
• The kaon semileptonic form factor with near physical domain wall quarks
• Leptoquark on $P\to {\ell }^{+}\nu$, FCNC and LFV
• A Mixed Tau-Electroproduction Sum Rule for V_us
• Unparticle-Induced Lepton Flavor Violating Decays τ^- ->l^- (V^0, ~P^0)
• Status of the Hadronic tau Decay Determination of |V_{us}|
• Hadronic decays of the tau lepton: Theoretical outlook
• New Results in Four and Five Loop QED calculations
• Theoretical overview on tau physics
• Tau Physics 2006: Summary & Outlook

Cited by in corpus (184)

• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of summer 2016
• QCD and strongly coupled gauge theories: challenges and perspectives
• B-physics anomalies: a guide to combined explanations
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2018
• Dressing L_mu - L_tau in Color
• Low-Energy Effective Field Theory below the Electroweak Scale: Operators and Matching
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of 2021
• Longitudinal short-distance constraints for the hadronic light-by-light contribution to $(g-2{)}_{\mu }$ with large-$N_c$ Regge models
• Global constraints on heavy neutrino mixing
• STCF Conceptual Design Report: Volume 1 -- Physics & Detector
• Lepton-flavour violating $B$ decays in generic $Z^{\prime }$ models
• Review of Lepton Universality tests in B decays
• Revisiting Lepton Flavour Universality in B Decays
• Lepton flavor violating Z' explanation of the muon anomalous magnetic moment
• Global Constraints on a Heavy Neutrino
• Phenomenology of an $SU(2)\times SU(2)\times U(1)$ model with lepton-flavour non-universality
• A Global Likelihood for Precision Constraints and Flavour Anomalies
• The CKM unitarity problem: A trace of new physics at the TeV scale?
• Global Fit to Modified Neutrino Couplings and the Cabibbo-Angle Anomaly
• Combined Explanations of the $b\to s{\mu }^{+}{\mu }^{-}$ and $b\to c{\tau }^{-}\bar{\nu }$ Anomalies: a General Model Analysis
• On the Importance of Electroweak Corrections for B Anomalies
• Beta decays as sensitive probes of lepton flavor universality
• Determination of the QCD Coupling from ALEPH $\tau$ Decay Data
• Addressing the B-physics anomalies in a fundamental Composite Higgs Model
• Low-energy phenomenology of scalar leptoquarks at one-loop accuracy
• Constraints on scalar leptoquarks from lepton and kaon physics
• The role of the $S_3$ GUT leptoquark in flavor universality and collider searches
• Lepton-flavor universality violation in $R_K$ and $R_{D^{(\ast )}}$ from warped space
• Global Electroweak Fit and Vector-Like Leptons in Light of the Cabibbo Angle Anomaly
• Hadronic tau decays as New Physics probes in the LHC era
• Thermal Dark Matter Through the Dirac Neutrino Portal
• Short-distance constraints on hadronic light-by-light scattering in the anomalous magnetic moment of the muon
• Baryogenesis from a dark first-order phase transition
• Probing CP violation with non-unitary mixing in long-baseline neutrino oscillation experiments: DUNE as a case study
• Addressing $R_{D^{(\ast )}}$, $R_{K^{(\ast )}}$, muon $g-2$ and ANITA anomalies in a minimal $R$-parity violating supersymmetric framework
• The Fermi constant from muon decay versus electroweak fits and CKM unitarity
• Semi-leptonic $B$-physics anomalies: a general EFT analysis within $U(2{)}^n$ flavor symmetry
• Full parameter scan of the Zee model: exploring Higgs lepton flavor violation
• Explaining $b\to s{\ell }^{+}{\ell }^{-}$ and the Cabibbo Angle Anomaly with a Vector Triplet
• Anatomy of $b\to c\tau \nu$ anomalies
• Loop level constraints on Seesaw neutrino mixing
• On the Statistical Treatment of the Cabibbo Angle Anomaly
• The QCD Renormalization Group Equation and the Elimination of Fixed-Order Scheme-and-Scale Ambiguities Using the Principle of Maximum Conformality
• Electron and muon $g-2$ anomalies in general flavour conserving two Higgs doublets models
• Scalar Leptoquarks in Leptonic Processes
• Correlating $W$-Boson Mass Shift with Muon $g-2$ in the 2HDM
• Revisiting R-parity violating interactions as an explanation of the B-physics anomalies
• Low-energy Effects of Lepton Flavour Universality Violation
• Unveiling Hidden Physics at the LHC
• $R_{K^{(\ast )}}$ and related $b\to s\ell \bar{\ell }$ anomalies in minimal flavor violation framework with $Z^{\prime }$ boson
• Light-Cone Sum Rules for $B\to K\pi$ Form Factors and Applications to Rare Decays
• Anomalous Higgs couplings in angular asymmetries of H --> Zl+l- and e+e- --> HZ
• Flavor Anomalies in Heavy Quark Decays
• Predictions on the second-class current decays ${\tau }^{-}\to {\pi }^{-}{\eta }^{(\prime )}{\nu }_{\tau }$
• Higher-order QCD corrections to hadronic $\tau$ decays from Padé approximants
• Effective approach to lepton observables: the seesaw case
• Revision of the LHCb Limit on Majorana Neutrinos
• Effective Theory and Simple Completions for Neutrino Interactions
• Semileptonic tau decays beyond the Standard Model
• Heavy Neutrinos and the Kinematics of Tau Decays
• A dispersive analysis of the pion vector form factor and ${\tau }^{-}\to K^{-}{K}_S{\nu }_{\tau }$ decay
• 750 GeV Composite Axion as the LHC Diphoton Resonance
• New Physics effects in leptonic and semileptonic decays
• Updated determination of chiral couplings and vacuum condensates from hadronic tau decay data
• Bottom-Flavored Mono-Tau Tails at the LHC
• Test of the universality of $\tau$ and $\mu$ lepton couplings in $W$-boson decays from $t\bar{t}$ events with the ATLAS detector
• Testing Lepton Flavor Universality with Pion, Kaon, Tau, and Beta Decays
• Combined analysis of the decays ${\tau }^{-}\to K_S{\pi }^{-}{\nu }_{\tau }$ and ${\tau }^{-}\to K^{-}\eta {\nu }_{\tau }$
• Exclusive hadronic tau decays as probes of non-SM interactions
• Muon and electron $g-2$ anomalies in a flavor conserving 2HDM with an oblique view on the CDF $M_W$ value
• Effective-field theory analysis of the ${\tau }^{-}\to (K\pi {)}^{-}{\nu }_{\tau }$ decays
• Correlating Tauonic B Decays to the Neutron EDM via a Scalar Leptoquark
• Implications for Electric Dipole Moments of a Leptoquark Scenario for the $B$-Physics Anomalies
• Novel method for the direct measurement of the tau lepton dipole moments
• Galactic center GeV gamma-ray excess from dark matter with gauged lepton numbers
• R-parity violating solutions to the $R_{D^{(\ast )}}$ anomaly and their GUT-scale unifications
• B-physics anomalies: The bridge between R-parity violating Supersymmetry and flavoured Dark Matter
• Precision physics with inclusive QCD processes
• Radiative corrections to $\tau \to \pi (K){\nu }_{\tau }[\gamma ]$: a reliable new physics test
• Constraints on the charged currents in general neutrino interactions with sterile neutrinos
• Testing Minimal Flavor Violation in Leptoquark Models of the $R_{K^{(\ast )}}$ Anomaly
• The Forward-Backward Asymmetry in $B\to D^{\ast }\ell \nu$: One more hint for Scalar Leptoquarks?
• Higher-order perturbative coefficients in QCD from series acceleration by conformal mappings
• Conformal mapping of the Borel plane: going beyond perturbative QCD
• From B-meson anomalies to Kaon physics with scalar leptoquarks
• Search for the anomalous electromagnetic moments of the tau lepton through electron-photon scattering at the CLIC
• CP asymmetry in $\tau \to K_S\pi {\nu }_{\tau }$ decays within the Standard Model and beyond
• Triangle singularity in ${\tau }^{-}\to {\nu }_{\tau }{\pi }^{-}{f}_0(980)$ ($a_0(980)$) decays
• What can we learn about light-meson interactions at electron-positron colliders?
• A model for the Singlet-Triplet Leptoquarks
• Five-body leptonic decays of muon and tau leptons
• Model-independent bounds probing on the electromagnetic dipole moments of the $\tau$-lepton at the CLIC
• Lattice determinations of the strong coupling
• Chiral sum rules and vacuum condensates from tau-lepton decay data
• Analysis of the anomalous electromagnetic moments of the tau lepton in $\gamma p$ collisions at the LHC
• Simultaneous interpretation of $K$ and $B$ anomalies in terms of chiral-flavorful vectors
• Long-lived light neutralinos at Belle II
• Updated global fit of the aligned two-Higgs-doublet model with heavy scalars
• Violations of Quark-Hadron Duality in Low-Energy Determinations of ${\alpha }_s$
• $R_{D^{(\ast )}}$ in custodial warped space
• Strong coupling constant and quark masses from lattice QCD
• Renormalons in integrated spectral function moments and ${\alpha }_s$ extractions
• $CP$ asymmetry in the angular distribution of $\tau \to K_S\pi {\nu }_{\tau }$ decays
• Widening the $U(1{)}_{L_{\mu }-L_{\tau }}$ $Z^{\prime }$ mass range for resolving the muon $g-2$ anomaly
• Effective comparison of neutrino-mass models
• A fake doublet solution to the muon anomalous magnetic moment
• $\tau$ decay into a pseudoscalar and an axial-vector meson
• Probing new charged scalars with neutrino trident production
• Purely flavor-changing Z' bosons and where they might hide
• ${\tau }^{-}\to {\eta }^{(\prime )}{\pi }^{-}{\nu }_{\tau }\gamma$ decays as backgrounds in the search for second class currents
• Radiative Neutrino Mass in Alternative Left-Right Model
• Lepton-flavor-violating semileptonic $\tau$ decay and $K\to \pi \nu \bar{\nu }$
• $CP$ asymmetry in the angular distributions of $\tau \to K_S\pi {\nu }_{\tau }$ decays -- II: general effective field theory analysis
• The ${\mu }^{+}{\mu }^{-}$ collider to sensitivity estimates on the magnetic and electric dipole moments of the tau-lepton
• Anomalous magnetic and weak magnetic dipole moments of the $\tau$ lepton in the simplest little Higgs model
• Comprehensive Analysis of Charged Lepton Flavour Violation in the Symmetry Protected Type-I Seesaw
• LIght scalars with lepton number to solve the $(g-2{)}_e$ anomaly
• The Singly-Charged Scalar Singlet as the Origin of Neutrino Masses
• Effective-field theory analysis of the ${\tau }^{-}\to K^{-}({\eta }^{(\prime )},K^0){\nu }_{\tau }$ decays
• Global Bounds on the Type-III Seesaw
• One-loop determination of $\tau \to \pi (K){\nu }_{\tau }[\gamma ]$ branching ratios and new physics tests
• Updated determination of ${\alpha }_s(m_{\tau }^2)$ from tau decays
• Search for the electromagnetic moments of the $\tau$ lepton in photon-photon collisions at the LHeC and the FCC-he
• Lepton-flavor universality limits in warped space
• The role of non-universal $Z$ couplings in explaining the $V_{us}$ anomaly
• Sensitivity of future lepton colliders and low-energy experiments to charged lepton flavor violation from bileptons
• Flavor Physics at the CEPC: a General Perspective
• "Could Charm (\& $\tau$) Transitions be the `Poor Princesses' of Deeper Understanding of Fundamental Dynamics?" -- or -- "Finding Novel Forces?"
• Probing Heavy Neutrino Magnetic Moments at the LHC using Long-Lived Particle Searches
• Direct CP violation in ${\tau }^{\pm }\to K^{\pm }{\rho }^0(\omega ){\nu }_{\tau }\to K^{\pm }{\pi }^{+}{\pi }^{-}{\nu }_{\tau }$
• New gauge boson Z' and lepton flavor violating decays and production of vector mesons
• Renormalization group improved implications of semileptonic operators in SMEFT
• Strong dynamics in a classically scale invariant extension of the Standard Model with flatland
• Michel parameters in the presence of massive Dirac and Majorana neutrinos
• Correlating New Physics Effects in Semileptonic $\Delta C=1$ and $\Delta S=1$ Processes
• Lepton Flavour Violation in Hadron Decays of the Tau Lepton in the Simplest Little Higgs Model
• Renormalization-scheme variation of a QCD perturbation expansion with tamed large-order behavior
• Decays of a bino-like particle in the low-mass regime
• Inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach to QCD
• Leading-order hadronic contributions to the electron and tau anomalous magnetic moments
• Chiral extrapolation and finite-volume dependence of the hyperon vector couplings
• Instanton-mediated baryon number violation in non-universal gauge extended models
• Feasibility study of $CP$ Violation in ${\tau }^{-}\to K_S{\pi }^{-}{\nu }_{\tau }$ decays at Super Tau Charm Facility
• Analytical determination of the QCD quark masses
• Constraints on the charged-current non-standard neutrino interactions induced by the gauge boson $W^{\prime }$
• Measurement of jet production in deep inelastic scattering and NNLO determination of the strong coupling at ZEUS
• Lepton-pair production in di-pion $\tau$ lepton decays
• Research on the electromagnetic and weak dipole moments of the tau-lepton at the Bestest Little Higgs Model
• Renormalization group improved $m_s$ and $|V_{us}|$ determination from hadronic $\tau$ decays
• Minimal Zee model for lepton $g-2$ and $W$-mass shifts
• Michel parameters for $\tau$ decays $\tau \to l\nu \bar{\nu }(l=e,\mu )$ in a general two Higgs doublet model with $\mu -\tau$ flavor violation
• Axial-vector transition form factors of the baryon octet to the baryon decuplet with flavor SU(3) symmetry breaking
• Muon $g-2$ Anomaly and Neutrino Magnetic Moments
• Resurgent representation of the Adler function in the large-${\beta }_0$ approximation of QCD
• Analysis of Dalitz decays with intrinsic parity violating interactions in resonance chiral perturbation theory
• Precision physics with QCD
• Status and progress of the HFLAV-Tau group activities
• Tests of quark-hadron duality in tau-decays
• Precise test of lepton flavour universality in $W$-boson decays into muons and electrons in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Constraints on $\tau$ electromagnetic moments via tau pair production at the Muon colliders
• About heavy neutrinos: Lepton-flavor violation in decays of charged leptons
• Status after the first LHC run: Looking for new directions in the physics landscape
• General Signals for Charged Lepton Flavor Violating Decays
• CP violation in two-meson Tau decays induced by heavy new physics
• Polarization effects in radiative decay of polarized $\tau$ lepton
• Theoretical overview of kaon decays
• Azimuthal distributions in radiative decay of polarized $\tau$ lepton
• Phenomenology of ${\tau }^{-}\to {\pi }^{-}{\nu }_{\tau }\gamma$ using LCSR
• Quark-hadron duality: pinched kernel approch
• Constraining EDM and MDM lepton dimension five interactions in the electroweak sector
• Test of lepton flavour universality in $W$-boson decays into electrons and $\tau$-leptons using $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• RPV SUSY effects in ${\tau }^{-}\to e^{-}({\mu }^{-})K\bar{K}$ Decays
• Implications of NSI constraints from ANTARES and IceCube on a simplified $Z^{\prime }$ model
• Towards the (Mexican) discovery of second class currents at Belle-II
• Constraints on the parameters of the neutrino extension of the Standard Model
• Polarized tau decay and CP violation in ultraperipheral heavy-ion collisions
• Analytical Inverse QCD Coupling Constant approach and its result for ${\alpha }_s$
• Probing charged lepton flavor violation with axion-like particles at Belle II
• Aligned Zee-Grimus-Neufeld model for $(g-2{)}_{\mu }$
• Resonance Chiral Lagrangians and alternative approaches to hadronic tau decays
• About The Polarized $\tau$ Lepton Radiative Decay
• Updated determinations of |V${}_{us}$| with tau decays using new recent estimates of radiative corrections for light-meson leptonic decay rates
• Workshop on Tau Lepton Physics: $30^{\mathbf{th}}$ Anniversary
• Can a Nonstandard Invisible Pair Mimic the Michel Distribution?