The anomalous $Zb\bar{b}$ couplings: From LEP to LHC

Abstract

The bottom quark forward-backward asymmetry ($A_{FB}^b$) data at LEP exhibits a long-standing discrepancy with the standard model prediction. We propose a novel method to probe the $Zb\bar{b}$ interactions through $gg\to Zh$ production at the LHC, which is sensitive to the axial-vector component of the $Zb\bar{b}$ couplings. We demonstrate that the $Zh$ data collected at the 13 TeV LHC can already resolve the apparent degeneracy of the anomalous $Zb\bar{b}$ couplings implied by the LEP precision electroweak measurements, with a strong dependence on the observed distribution of the $Z$ boson transverse momentum. We also show the potential of the HL-LHC to either verify or exclude the anomalous $Zb\bar{b}$ couplings observed at LEP through measuring the $Zh$ production rate at the HL-LHC, and this conclusion is not sensitive to possible new physics contribution induced by top quark or Higgs boson anomalous couplings in the loop.

6 pages, 6 figurs, matches version published in PRL

References in corpus (16)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• A custodial symmetry for Zbb
• The global electroweak fit at NNLO and prospects for the LHC and ILC
• Measurements of $WH$ and $ZH$ production in the $H\to b\bar{b}$ decay channel in $pp$ collisions at 13 TeV with the ATLAS detector
• Higgs boson production cross-section measurements and their EFT interpretation in the $4\ell$ decay channel at $\sqrt{s}$ = 13 TeV with the ATLAS detector
• Measurement of the $t\bar{t}Z$ and $t\bar{t}W$ cross sections in proton-proton collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Measurement of the associated production of a Higgs boson decaying into $b$-quarks with a vector boson at high transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Combined Explanation of the $Z\to b\bar{b}$ Forward-Backward Asymmetry, the Cabibbo Angle Anomaly, $\tau \to \mu \nu \nu$ and $b\to s{\ell }^{+}{\ell }^{-}$ Data
• Limiting Top-Higgs Interaction and Higgs-Boson Width from Multi-Top Productions
• On top quark mass effects to $gg\to ZH$ at NLO
• $ZH$ production in gluon fusion: two-loop amplitudes with full top quark mass dependence
• Observation of the associated production of a top quark and a $Z$ boson in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
• Measurement of $VH$, $H\to b\bar{b}$ production as a function of the vector-boson transverse momentum in 13 TeV $pp$ collisions with the ATLAS detector
• Virtual corrections to $gg\to ZH$ in the high-energy and large-$m_t$ limits
• Higgs Boson Decay to Light Jets at the LHC
• Probing $Zt\bar{t}$ couplings using $Z$ boson polarization in $ZZ$ production at hadron colliders

Cited by in corpus (14)

• More Synergies from Beauty, Top, $Z$ and Drell-Yan Measurements in SMEFT
• ZH production in gluon fusion at NLO in QCD
• On the NLO QCD Corrections to Gluon-Initiated ZH Production
• Anomalous couplings in associated $VH$ production with Higgs decay to massive $b$ quarks at NNLO in QCD
• Probing Top-quark Operators with Precision Electroweak Measurements
• Probing composite Higgs boson substructure at the HL-LHC
• Revisiting $\mathbf{Vh}(\to \mathbf{b}\bar{\mathbf{b}})$ at the LHC and FCC-hh
• Probing the $H\gamma \gamma$ coupling via Higgs exclusive decay into quarkonia plus a photon at the HL-LHC
• Top quark effective couplings from top-pair tagged photoproduction in $p{e}^{-}$ collisions
• Probing top-quark electroweak couplings indirectly at the Electron-Ion Collider
• Fitting the $Zb\bar{b}$ vertex in the two-Higgs-doublet model and in the three-Higgs-doublet model
• Accommodating the CDF W-boson Mass Measurement in the Beautiful Mirror Model
• The $Zb\bar{b}$ vertex in a left-right model
• Tracing the bottom electroweak dipole operators at future lepton colliders