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Measurement of $\sin^2\theta^{\rm lept}_{\rm eff}$ using $e^+e^-$ pairs from $\gamma^*/Z$ bosons produced in $p\bar{p}$ collisions at a center-of-momentum energy of 1.96 TeV

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.

Phys.Rev.D 93 (2016) 112016, 2016.

Inspire Record 1456804 DOI 10.17182/hepdata.78542

At the Fermilab Tevatron proton-antiproton ($p\bar{p}$) collider, Drell-Yan lepton pairs are produced in the process $p \bar{p} \rightarrow e^+e^- + X$ through an intermediate $\gamma^*/Z$ boson. The forward-backward asymmetry in the polar-angle distribution of the $e^-$ as a function of the $e^+e^-$-pair mass is used to obtain $\sin^2\theta^{\rm lept}_{\rm eff}$, the effective leptonic determination of the electroweak-mixing parameter $\sin^2\theta_W$. The measurement sample, recorded by the Collider Detector at Fermilab (CDF), corresponds to 9.4~fb$^{-1}$ of integrated luminosity from $p\bar{p}$ collisions at a center-of-momentum energy of 1.96 TeV, and is the full CDF Run II data set. The value of $\sin^2\theta^{\rm lept}_{\rm eff}$ is found to be $0.23248 \pm 0.00053$. The combination with the previous CDF measurement based on $\mu^+\mu^-$ pairs yields $\sin^2\theta^{\rm lept}_{\rm eff} = 0.23221 \pm 0.00046$. This result, when interpreted within the specified context of the standard model assuming $\sin^2 \theta_W = 1 - M_W^2/M_Z^2$ and that the $W$- and $Z$-boson masses are on-shell, yields $\sin^2\theta_W = 0.22400 \pm 0.00045$, or equivalently a $W$-boson mass of $80.328 \pm 0.024 \;{\rm GeV}/c^2$.

2 data tables

Table 1

Best-fit values of $\sin^2\theta_{\rm eff}^{\rm lept}$, $\sin^2\theta_W$ and $M_W$(indirect) from the $ee$-channel measurement of $A_{\rm fb}$ and a combination with the previous CDF measurement based on muon pairs.

Table 2

Fully corrected $A_{fb}$ measurement for electron pairs with $|y|<1.7$. The measurement uncertainties are bin-by-bin unfolding estimates.

Indirect measurement of $\sin^2 \theta_W$ (or $M_W$) using $\mu^+\mu^-$ pairs from $\gamma^*/Z$ bosons produced in $p\bar{p}$ collisions at a center-of-momentum energy of 1.96 TeV

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.

Phys.Rev.D 89 (2014) 072005, 2014.

Inspire Record 1280719 DOI 10.17182/hepdata.64738

Drell-Yan lepton pairs are produced in the process $p\bar{p} \rightarrow \mu^+\mu^- + X$ through an intermediate $\gamma^*/Z$ boson. The forward-backward asymmetry in the polar-angle distribution of the $\mu^-$ as a function of the invariant mass of the $\mu^+\mu^-$ pair is used to obtain the effective leptonic determination $\sin^2 \theta^{lept}_{eff}$ of the electroweak-mixing parameter $\sin^2 \theta_W$, from which the value of $\sin^2 \theta_W$ is derived assuming the standard model. The measurement sample, recorded by the Collider Detector at Fermilab (CDF), corresponds to 9.2 fb-1 of integrated luminosity from $p\bar{p}$ collisions at a center-of-momentum energy of 1.96 TeV, and is the full CDF Run II data set. The value of $\sin^2 \theta^{lept}_{eff}$ is found to be 0.2315 +- 0.0010, where statistical and systematic uncertainties are combined in quadrature. When interpreted within the context of the standard model using the on-shell renormalization scheme, where $\sin^2 \theta_W = 1 - M_W^2/M_Z^2$, the measurement yields $\sin^2 \theta_W$ = 0.2233 +- 0.0009, or equivalently a W-boson mass of 80.365 +- 0.047 GeV/c^2. The value of the W-boson mass is in agreement with previous determinations in electron-positron collisions and at the Tevatron collider.

4 data tables

Table 1

The measured value of SIN**2(THETAEFF(LEPTON)).

Table 2

The measured value of SIN**2(THETA(W)).

Table 3

The measured value of M(W).

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rivet Analysis
A precise measurement of the tau polarisation at LEP-1.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Eur.Phys.J.C 14 (2000) 585-611, 2000.

Inspire Record 511443 DOI 10.17182/hepdata.49001

The$\tau$polarisation has been studied with the${\rm e^+e^-}\to \tau^+\tau^-$data collected by the DELPHI detector at LEP in

2 data tables

Table 1

The errors are statistical and systematic combined in quadrature.

Table 2

No description provided.

Measurement of the strange quark forward-backward asymmetry around the Z0 peak.

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Eur.Phys.J.C 14 (2000) 613-631, 2000.

Inspire Record 509441 DOI 10.17182/hepdata.49013

A precise measurement of the strange quark forward-backward asymmetry used 3.2M multihadronic events around the Z$^0$peak collected by the DELPHI experiment from 1

2 data tables

Table 1

No description provided.

Table 2

Parity violating coupling, COUPLING(NAME=A_S) = (2*V_S*A_S)/(V_S**2+A_S**2).

Measurement of the b forward-backward asymmetry and mixing using high-p(T) leptons.

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.

Phys.Lett.B 384 (1996) 96009264 414-426, 1996.

Inspire Record 419905 DOI 10.17182/hepdata.47806

The B⁰ - B̄⁰ average mixing parameter $χ$ and b forward-backward asymmetry AFB⁰(b) are measured from a sample of about 4 200 000 Z → qq̄ events recorded with the ALEPH detector at LEP in the years 1990–1995. High transverse momentum electrons and muons produced in b semileptonic decays provide the tag of the quark flavour and of its charge. The average mixing parameter and the pole b asymmetry are measured to be $χ$ = 0.1246 ± 0.0051stat ± 0.0052syst, AFB⁰(b) = 0.1008 ± 0.0043stat ± 0.0028syst. The value of sin²θw^eff = 0.23198 ± 0.00092 is extracted from the asymmetry measurement.

2 data tables

Table 1

ASYM(N=FB,C=OBSERVED) is observed asymmetry including BQ, CQ and backround.

Table 2

No description provided.

Determination of sin**2 theta(w)(eff) using jet charge measurements in hadronic Z decays

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.

Z.Phys.C 71 (1996) 357-378, 1996.

Inspire Record 416137 DOI 10.17182/hepdata.47832

None

1 data table

Table 1

The first sytematic error is due to the experimental uncertainties, whilst the second is due to the uncertainties in the quark charge separations.

The Forward - backward asymmetry for charm quarks at the Z pole

The ALEPH collaboration Buskulic, D. ; Casper, D. ; De Bonis, I. ; et al.

Phys.Lett.B 352 (1995) 479-486, 1995.

Inspire Record 394753 DOI 10.17182/hepdata.47932

From 1.4 million hadronic Z decays collected by the ALEPH detector at LEP, an enriched sample of Z → cc̄ events is extracted by requiring the presence of a high momentum D ∗± . The charm quark forward-backward charge asymmetry at the Z pole is measured to be A FB 0. c = (8.0 ± 2.4) % corresponding to an effective electroweak mixing angle of sin 2 θ W eff = 0.2302 ± 0.0054.

2 data tables

Table 1

Value of SIN2TW(eff) from CQ-quark asymmetries.

Table 2

No description provided.

Measurements of the tau polarization in Z0 decays

The DELPHI collaboration Abreu, P. ; Adam, W. ; Adye, T. ; et al.

Z.Phys.C 67 (1995) 183-202, 1995.

Inspire Record 393793 DOI 10.17182/hepdata.47961

A sample of Z0→τ+τ− events observed in the DELPHI detector at LEP in 1991 and 1992 is analysed to measure the τ polarisation in the exclusive decay channels$ev\bar v$,$\mu v\bar v$, πν, ρν and a1ν. The τ polarisation is also measured with an inclusive hadronic analysis which benefits from a higher efficiency and a better systematic precision than the use of the exclusive decay modes. The results have been combined with those published on the 1990 data. A measurement of the τ polarisation as a function of production angle yields the values for the mean τ polarisation 〈P〉τ=−0.148±0.022 and for the Z0 polarisationPZ=−0.136±0.027. These results are used to determine the ratio of vector to axial-vector effective couplings for taus$\bar v_\tau/\bar a_\tau= 0.074 \pm 0.011$, and for electrons$\bar v_e /\bar a_e= 0.068 \pm 0.014$, compatible with e-τ universality. With the assumption of lepton universality, the ratio of vector to axial-vector effective couplings for leptons$\bar v_l /\bar a_l= 0.072 \pm 0.008$ is obtained, implying a value of the effective weak mixing angle sin2θefflept=0.2320±0.0021.

10 data tables

Table 1

Results are for both TAU+ and TAU- decay.

Table 2

The systematic error contains a systematic error of 0.003 common to all channels.

Table 3

Errors are statistical only.