SMEFT Analysis of $m_W$

Abstract

We use the Fitmaker tool to incorporate the recent CDF measurement of $m_W$ in a global fit to electroweak, Higgs, and diboson data in the Standard Model Effective Field Theory (SMEFT) including dimension-6 operators at linear order. We find that including any one of the SMEFT operators ${\mathcal{O}}_{HWB}$, ${\mathcal{O}}_{HD}$, ${\mathcal{O}}_{\ell \ell }$ or ${\mathcal{O}}_{H\ell }^{(3)}$ with a non-zero coefficient could provide a better fit than the Standard Model, with the strongest pull for ${\mathcal{O}}_{HD}$ and no tension with other electroweak precision data. We then analyse which tree-level single-field extensions of the Standard Model could generate such operator coefficients with the appropriate sign, and discuss the masses and couplings of these fields that best fit the CDF measurement and other data. In particular, the global fit favours either a singlet $Z^{\prime }$ vector boson, a scalar electroweak triplet with zero hypercharge, or a vector electroweak triplet with unit hypercharge, followed by a singlet heavy neutral lepton, all with masses in the multi-TeV range for unit coupling.

23 pages, 8 figures. References added, extended and clarified discussions, added discussion of the impact of enlarged uncertainties according to PDG prescription. Version accepted for publication in JHEP

References in corpus (16)

• Top, Higgs, Diboson and Electroweak Fit to the Standard Model Effective Field Theory
• A Monte Carlo global analysis of the Standard Model Effective Field Theory: the top quark sector
• Compilation of low-energy constraints on 4-fermion operators in the SMEFT
• Observable Effects of General New Scalar Particles
• Top and Beauty synergies in SMEFT-fits at present and future colliders
• Obscure Higgs boson at Colliders
• Low energy SUSY confronted with new measurements of W-boson mass and muon g-2
• SMEFT analysis of vector boson scattering and diboson data from the LHC Run II
• The Flavor of UV Physics
• The top quark electro-weak couplings after LHC Run 2
• Interdependence of the new "MUON G-2" Result and the $W$-Boson Mass
• Unified Explanation of the Anomalies in Semi-Leptonic $B$ decays and the $W$ Mass
• Global Fits of Third Family Hypercharge Models to Neutral Current B-Anomalies and Electroweak Precision Observables
• The Singly-Charged Scalar Singlet as the Origin of Neutrino Masses
• Flavorful Electroweak Precision Observables in the Standard Model Effective Field Theory
• Higgs probes of top quark contact interactions and their interplay with the Higgs self-coupling