Measurement of the inclusive leptonic asymmetry in top-quark pairs that decay to two charged leptons at CDF

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.
Phys.Rev.Lett. 113 (2014) 042001, 2014.
Inspire Record 1290358 DOI 10.17182/hepdata.64422
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First measurement of the forward-backward asymmetry in bottom-quark pair production at high mass

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.
Phys.Rev. D92 (2015) 032006, 2015.
Inspire Record 1364882 DOI 10.17182/hepdata.73682

We measure the particle-level forward-backward production asymmetry in bb¯ pairs with masses (mbb¯) larger than 150  GeV/c2, using events with hadronic jets and employing jet charge to distinguish b from b¯. The measurement uses 9.5  fb-1 of pp¯ collisions at a center-of-mass energy of 1.96 TeV recorded by the CDF II detector. The asymmetry as a function of mbb¯ is consistent with zero, as well as with the predictions of the standard model. The measurement disfavors a simple model including an axigluon with a mass of 200  GeV/c2, whereas a model containing a heavier 345  GeV/c2 axigluon is not excluded.

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Measurement of the forward–backward asymmetry of top-quark and antiquark pairs using the full CDF Run II data set

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.
Phys.Rev. D93 (2016) 112005, 2016.
Inspire Record 1424841 DOI 10.17182/hepdata.77054

We measure the forward–backward asymmetry of the production of top-quark and antiquark pairs in proton-antiproton collisions at center-of-mass energy s=1.96  TeV using the full data set collected by the Collider Detector at Fermilab (CDF) in Tevatron Run II corresponding to an integrated luminosity of 9.1  fb-1. The asymmetry is characterized by the rapidity difference between top quarks and antiquarks (Δy) and measured in the final state with two charged leptons (electrons and muons). The inclusive asymmetry, corrected to the entire phase space at parton level, is measured to be AFBtt¯=0.12±0.13, consistent with the expectations from the standard model (SM) and previous CDF results in the final state with a single charged lepton. The combination of the CDF measurements of the inclusive AFBtt¯ in both final states yields AFBtt¯=0.160±0.045, which is consistent with the SM predictions. We also measure the differential asymmetry as a function of Δy. A linear fit to AFBtt¯(|Δy|), assuming zero asymmetry at Δy=0, yields a slope of α=0.14±0.15, consistent with the SM prediction and the previous CDF determination in the final state with a single charged lepton. The combined slope of AFBtt¯(|Δy|) in the two final states is α=0.227±0.057, which is 2.0σ larger than the SM prediction.

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Measurement of the forward-backward asymmetry in low-mass bottom-quark pairs produced in proton-antiproton collisions

The CDF collaboration Aaltonen, Timo Antero ; Amerio, Silvia ; Amidei, Dante E ; et al.
Phys.Rev. D93 (2016) 112003, 2016.
Inspire Record 1416824 DOI 10.17182/hepdata.77045

We report a measurement of the forward-backward asymmetry, AFB, in bb¯ pairs produced in proton-antiproton collisions and identified by muons from semileptonic b-hadron decays. The event sample is collected at a center-of-mass energy of s=1.96  TeV with the CDF II detector and corresponds to 6.9  fb-1 of integrated luminosity. We obtain an integrated asymmetry of AFB(bb¯)=(1.2±0.7)% at the particle level for b-quark pairs with invariant mass, mbb¯, down to 40  GeV/c2 and measure the dependence of AFB(bb¯) on mbb¯. The results are compatible with expectations from the standard model.

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A Determination of $\sin^2\theta$ from the forward - backward asymmetry in $p\bar{p} \to Z^0 X \to e^+e^- X$ interactions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 67 (1991) 1502-1506, 1991.
Inspire Record 317764 DOI 10.17182/hepdata.19899
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Measurement of $d(\sigma)/dM$ and forward-backward charge asymmetry for high mass Drell-Yan $e^+e^-$ pairs from $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Affolder, T. ; Akimoto, H. ; Akopian, A. ; et al.
Phys.Rev.Lett. 87 (2001) 131802, 2001.
Inspire Record 558278 DOI 10.17182/hepdata.42899

We report on a measurement of the mass dependence of the forward-backward charge asymmetry, A_FB, and production cross section dsigma/dM for e+e- pairs with mass M_ee>40 GeV/c2. The data sample consists of 108 pb-1 of p-pbar collisions at sqrt(s)=1.8 TeV taken by the Collider Detector at Fermilab during 1992-1995. The measured asymmetry and dsigma/dM are compared with the predictions of the Standard Model and a model with an extra Z' gauge boson.

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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. D89 (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.

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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. D93 (2016) 112016, 2016.
Inspire Record 1456804 DOI 10.17182/hepdata.78542

At the Fermilab Tevatron proton-antiproton (pp¯) collider, Drell-Yan lepton pairs are produced in the process pp¯→e+e-+X through an intermediate γ*/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 sin2θefflept, the effective leptonic determination of the electroweak-mixing parameter sin2θW. The measurement sample, recorded by the Collider Detector at Fermilab (CDF), corresponds to 9.4  fb-1 of integrated luminosity from pp¯ collisions at a center-of-momentum energy of 1.96 TeV, and is the full CDF Run II data set. The value of sin2θefflept is found to be 0.23248±0.00053. The combination with the previous CDF measurement based on μ+μ- pairs yields sin2θefflept=0.23221±0.00046. This result, when interpreted within the specified context of the standard model assuming sin2θW=1-MW2/MZ2 and that the W- and Z-boson masses are on-shell, yields sin2θW=0.22400±0.00045, or equivalently a W-boson mass of 80.328±0.024  GeV/c2.

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The Charge asymmetry in $W$ boson decays produced in $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Albrow, M.G. ; Amidei, D. ; et al.
Phys.Rev.Lett. 74 (1995) 850-854, 1995.
Inspire Record 379592 DOI 10.17182/hepdata.42427

The charge asymmetry has been measured using $19,039W$ decays recorded by the CDF detector during the 1992-93 run of the Tevatron Collider. The asymmetry is sensitive to the ratio of $d$ and $u$ quark distributions to $x<0.01$ at $Q~2 \approx M_W~2$, where nonperturbative effects are minimal. It is found that of the two current sets of parton distributions, those of Martin, Roberts and Stirling (MRS) are favored over the sets most recently produced by the CTEQ collaboration. The $W$ asymmetry data provide a stronger constraints on $d/u$ ratio than the recent measurements of $F_2~{\mu n}/F_2~{\mu p}$ which are limited by uncertainties originating from deutron corrections.

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Lepton asymmetry in W decays from $\bar{p}p$ collisions at $\sqrt{s} = 1.8$ TeV

The CDF collaboration Abe, F. ; Amidei, Dante E. ; Apollinari, G. ; et al.
Phys.Rev.Lett. 68 (1992) 1458-1462, 1992.
Inspire Record 323033 DOI 10.17182/hepdata.19880
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