Complete electroweak two-loop corrections to Z boson production and decay

Abstract

This article presents results for the last unknown two-loop contributions to the $Z$-boson partial widths and $Z$-peak cross-section. These are the so-called bosonic electroweak two-loop corrections, where "bosonic" refers to diagrams without closed fermion loops. Together with the corresponding results for the $Z$-pole asymmetries $A_l,A_b$, which have been presented earlier, this completes the theoretical description of $Z$-boson precision observables at full two-loop precision within the Standard Model. The calculation has been achieved through a combination of different methods: (a) numerical integration of Mellin-Barnes representations with contour rotations and contour shifts to improve convergence; (b) sector decomposition with numerical integration over Feynman parameters; (c) dispersion relations for sub-loop insertions. Numerical results are presented in the form of simple parameterization formulae for the total width, ${\Gamma }_{\mathrm{Z}}$, partial decay widths ${\Gamma }_{e,\mu },{\Gamma }_{\tau },{\Gamma }_{\nu },{\Gamma }_u,{\Gamma }_c,{\Gamma }_{d,s},{\Gamma }_b$, branching ratios $R_l,R_c,R_b$ and the hadronic peak cross-section, ${\sigma }_{\mathrm{had}}^0$. Theoretical intrinsic uncertainties from missing higher orders are also discussed.

10 pages

References in corpus (14)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• The muon $g-2$ and $\alpha (M_Z^2)$: a new data-based analysis
• Hadronic Z- and tau-Decays in Order alpha_s^4
• On the Resolution of Singularities of Multiple Mellin-Barnes Integrals
• AMBRE - a Mathematica package for the construction of Mellin-Barnes representations for Feynman integrals
• Electroweak two-loop corrections to the effective weak mixing angle
• Single Scale Tadpoles and O(GF mt^2 as^3) Corrections to the rho Parameter
• Four-Loop QCD Corrections to the Rho Parameter
• The two-loop electroweak bosonic corrections to ${\sin }^2{\theta }_{\mathrm{eff}}^{\mathrm{b}}$
• Numerical Evaluation of Tensor Feynman Integrals in Euclidean Kinematics
• Bosonic Corrections to The Effective Weak Mixing Angle at O(alpha^2)
• The effective electroweak mixing angle ${\sin }^2{\theta }_{eff}$ with two-loop bosonic contributions
• S-matrix approach to the Z resonance
• 30 years, some 700 integrals, and 1 dessert, or: Electroweak two-loop corrections to the Zbb vertex

Cited by in corpus (34)

• Collider Physics at the Precision Frontier
• $\text{HEPfit}$: a Code for the Combination of Indirect and Direct Constraints on High Energy Physics Models
• Combined collider constraints on neutralinos and charginos
• Impact of the recent measurements of the top-quark and W-boson masses on electroweak precision fits
• Improved Bhabha cross section at LEP and the number of light neutrino species
• A frequentist analysis of three right-handed neutrinos with GAMBIT
• Global analysis of electroweak data in the Standard Model
• Electroweak and QCD Corrections to $Z$ and $W$ pole observables in the SMEFT
• Electroweak Precision Tests of the Standard Model after the Discovery of the Higgs Boson
• Electroweak pseudo-observables and Z-boson form factors at two-loop accuracy
• Violation of custodial symmetry from W-boson mass measurements
• The Importance of Flavor in SMEFT Electroweak Precision Fits
• GAMBIT and its Application in the Search for Physics Beyond the Standard Model
• Locally finite two-loop amplitudes for off-shell multi-photon production in electron-positron annihilation
• Accurate simulation of W, Z and Higgs boson decays in Sherpa
• Precision physics with inclusive QCD processes
• $W$-Boson Mass, Electroweak Precision Tests and SMEFT
• New physics interpretation of $W$-boson mass anomaly
• Evaluation of multi-loop multi-scale Feynman integrals for precision physics
• Leading fermionic three-loop corrections to electroweak precision observables
• QED challenges at FCC-ee precision measurements
• Two-Loop Electroweak Corrections with Fermion Loops to $e^{+}{e}^{-}\to ZH$
• Computational challenges for multi-loop collider phenomenology
• GRIFFIN: A C++ library for electroweak radiative corrections in fermion scattering and decay processes
• Mixed EW-QCD leading fermionic three-loop corrections at $\mathcal{O}({\alpha }_s{\alpha }^2)$ to electroweak precision observables
• $Z$-boson hadronic decay width up to $\mathcal{O}({\alpha }_s^4)$-order QCD corrections using the single-scale approach of the principle of maximum conformality
• Wave packets in QFT: leading order width corrections to decay rates and clock behaviour under Lorentz boosts
• Top and bottom quark forward-backward asymmetries at next-to-next-to-leading order QCD in (un)polarized electron positron collisions
• TASI 2020 Lectures on Precision Tests of the Standard Model
• CREDO project
• Towards a Fully Automated Differential ${\text{NNLO}}_{\text{EW}}$ Generator for Lepton Colliders
• Leading fermionic three-loop corrections to electroweak precision observables
• Precision Theory of Electroweak Interactions
• Monte Carlo Event Generators for Future Lepton Colliders