${\mathit {\mathit t}}$-quark EW Couplings

${{\mathit W}}$ helicity fractions in top decays. ${{\mathit F}_{{{0}}}}$ is the fraction of longitudinal and ${{\mathit F}_{{{+}}}}$ the fraction of right-handed ${{\mathit W}}$ bosons. ${{\mathit F}_{{{{V+A}}}}}$ is the fraction of $\mathit V+\mathit A$ current in top decays. The effective Lagrangian (cited by ABAZOV 2008AI) has terms f${}^{L}_{1}$ and f${}^{R}_{1}$ for $\mathit V−\mathit A$ and $\mathit V+\mathit A$ couplings, f${}^{L}_{2}$ and f${}^{R}_{2}$ for tensor couplings with b$_{R}$ and b$_{L}$ respectively.

Chromo-magnetic dipole moment ${{\mathit \mu}_{{{t}}}}={{\mathit g}_{{{s}}}}\hat{{\mathit\mu}}_{t}/{\mathit m}_{{{\mathit t}}}$

INSPIRE   PDGID:
Q007CMD
VALUE CL% DOCUMENT ID TECN  COMMENT
• • We do not use the following data for averages, fits, limits, etc. • •
$-0.024$ ${}^{+0.013}_{-0.009}$ ${}^{+0.016}_{-0.011}$ 1
SIRUNYAN
2020AM
CMS ${{\mathit \ell}}$+jets
$-0.014<\hat{{\mathit\mu}}_{t}<0.004$ 95 2
SIRUNYAN
2019BX
CMS ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)
$-0.053<Re(\hat{{\mathit\mu}}_{t})<0.026$ 95 3
KHACHATRYAN
2016AI
CMS ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)
1  SIRUNYAN 2020AM based on 35.9 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 13 TeV. ${{\mathit t}}{{\overline{\mathit t}}}$ with low and high boosts are reconstructed through a fit of the kinematic distributions. The ${{\mathit q}}{{\overline{\mathit q}}}$ initial subprocess is separated using different dependencies of the distributions on the initial states, and the linearized forward-backward asymmetry is measured to be $\mathit A{}^{(1)}_{FB}$ = $0.048$ ${}^{+0.095}_{-0.087}{}^{+0.020}_{-0.029}$.
2  SIRUNYAN 2019BX based on 35.9 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 13 TeV. A set of parton-level normalized differential cross sections is measured to extract coefficients of the spin-dependent ${{\mathit t}}{{\overline{\mathit t}}}$ production density matrix. The coefficients are compared with the NLO MC simulations and with the NLO QCD calculation including EW corrections.
3  KHACHATRYAN 2016AI based on 19.5 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 8 TeV, using lepton angular distributions as a function of the ${{\mathit t}}{{\overline{\mathit t}}}$-system kinematical variables.
References