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${\mathit {\mathit t}}$-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.

Spin Correlation in ${{\mathit t}}{{\overline{\mathit t}}}$ Production in ${{\mathit p}}{{\mathit p}}$ Collisions

Spin correlation, f$_{SM}$, measures the strength of the correlation between the spins of the pair produced ${{\mathit t}}{{\overline{\mathit t}}}$. f$_{SM}$ =1 for the SM, while f$_{SM}$ =0 for no spin correlation.

VALUE

DOCUMENT ID

TECN

COMMENT

• • We do not use the following data for averages, fits, limits, etc. • •

$0.90$ $\pm0.07$ $\pm0.09$ $\pm0.01$

CMS

$\mathit C_{kk}$ in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$1.13$ $\pm0.32$ $\pm0.32$ ${}^{+0.10}_{-0.13}$

CMS

$\mathit C_{rr}$ in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$1.01$ $\pm0.04$ $\pm0.05$ $\pm0.01$

CMS

$\mathit C_{nn}$ in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$0.94$ $\pm0.17$ $\pm0.26$ $\pm0.01$

CMS

$\mathit C_{rk}+\mathit C_{kr}$ in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$0.98$ $\pm0.03$ $\pm0.04$ $\pm0.01$

CMS

($\mathit C_{kk}+\mathit C_{rr}+\mathit C_{nn})/$3 in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$0.74$ $\pm0.07$ $\pm0.19$ ${}^{+0.06}_{-0.08}$

CMS

$\mathit A{}^{lab}_{cos \phi }$ in ${{\mathit \ell}}{{\mathit \ell}}+{}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$1.05$ $\pm0.03$ $\pm0.08$ ${}^{+0.09}_{-0.12}$

CMS

$\mathit A_{\vert \Delta \phi ({{\mathit \ell}} {{\mathit \ell}})\vert }$ in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$1.12$ ${}^{+0.12}_{-0.15}$

CMS

${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j (${}\geq{}1{{\mathit b}}$)

$0.72$ $\pm0.08$ ${}^{+0.15}_{-0.13}$

CMS

${{\mathit \mu}}$ + 4,5j

$1.20$ $\pm0.05$ $\pm0.13$

ATLS

$\Delta \phi ({{\mathit \ell}}{{\mathit \ell}}$) in ${{\mathit \ell}}{{\mathit \ell}}+{}\geq{}$2j(${}\geq{}1{{\mathit b}}$)

$1.19$ $\pm0.09$ $\pm0.18$

ATLS

$\Delta \phi ({{\mathit \ell}}{{\mathit \ell}}$) in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j events

$1.12$ $\pm0.11$ $\pm0.22$

ATLS

$\Delta \phi ({{\mathit \ell}}{{\mathit j}}$) in ${{\mathit \ell}}$ + ${}\geq{}$4j events

$0.87$ $\pm0.11$ $\pm0.14$

ATLS

S-ratio in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j events

$0.75$ $\pm0.19$ $\pm0.23$

ATLS

cos$\theta ({{\mathit \ell}^{+}}$)cos$\theta ({{\mathit \ell}^{-}}$) in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j events

$0.83$ $\pm0.14$ $\pm0.18$

ATLS

cos$\theta ({{\mathit \ell}^{+}}$)cos$\theta ({{\mathit \ell}^{-}}$) in ${{\mathit \ell}}{{\mathit \ell}}$ + ${}\geq{}$2j events

¹

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 sensitive to coefficients of the spin-dependent ${{\mathit t}}{{\overline{\mathit t}}}$ production density matrix is measured. The distributions and coefficients are compared with the NLO MC simulations and with the NLO QCD calculation including EW corrections. Three errors are from statistics, experimental systematics, and theory.

²	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.

³	KHACHATRYAN 2016X based on 19.7 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 8 TeV. Uses a template fit method. Spin correlation strength in the helicity basis is given by $\mathit A_{{\mathrm {hel}}}$ = $0.23$ $\pm0.03$ ${}^{+0.05}_{-0.04}$.

⁴

AAD 2015J based on 20.3 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ = 8 TeV. Uses a fit including a linear superposition of ${{\mathit \Delta}}{{\mathit \phi}}$ distribution from the SM NLO simulation with coefficient ${{\mathit f}_{{{SM}}}}$ and from ${{\mathit t}}{{\overline{\mathit t}}}$ simulation without spin correlation with coefficient (1 $−$ ${{\mathit f}_{{{SM}}}}$).

⁵	Based on 4.6 fb${}^{-1}$ of ${{\mathit p}}{{\mathit p}}$ data at $\sqrt {s }$ =7 TeV. The results are for ${\mathit m}_{{{\mathit t}}}$ = 172.5 GeV.

⁶	The S-ratio is defined as the SM spin correlation in the like-helicity gluon-gluon collisions normalized to the no spin correlation case; see eq.(6) for the LO expression.

⁷	The polar angle correlation along the helicity axis.

⁸	The polar angle correlation along the direction which maximizes the correlation.

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