$\mathit A_{FB}$ of ${{\mathit t}}{{\overline{\mathit t}}}$ in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV

INSPIRE   PDGID:
Q007TFB
$\mathit A_{FB}$ = Forward-backward asymmetry.
VALUE (%) DOCUMENT ID TECN  COMMENT
• • We do not use the following data for averages, fits, limits, etc. • •
$12.8$ $\pm2.1$ $\pm1.4$ 1
AALTONEN
2018
TEVA CDF, D0 combination
$17.5$ $\pm5.6$ $\pm3.1$ 2
ABAZOV
2015K
 D0 $\mathit A{}^{{{\mathit \ell}}}_{FB}$ in ${{\mathit \ell}}{{\mathit \ell}}$ +$\not E_T+{}\geq{}$2j(${}\geq{}1{{\mathit b}}$)
$7.2$ $\pm6.0$ 3
AALTONEN
2014F
 CDF $\mathit A{}^{{{\mathit \ell}}}_{FB}$ in dilepton channel (${{\mathit \ell}}{{\mathit \ell}}+\not E_T+{}\geq{}$2j)
$7.6$ $\pm8.2$ 3
AALTONEN
2014F
 CDF $\mathit A{}^{{{\mathit \ell}}{{\mathit \ell}}}_{FB}$ in dilepton channel (${{\mathit \ell}}{{\mathit \ell}}+\not E_T+{}\geq{}$2j)
$4.2$ $\pm2.3$ ${}^{+1.7}_{-2.0}$ 4
ABAZOV
2014G
 D0 $\mathit A{}^{{{\mathit \ell}}}_{FB}$ (${{\mathit \ell}}$ + $\not E_T+{}\geq{}$3j (0,1${}\geq{}2{{\mathit b}}$))
$10.6$ $\pm3.0$ 5
ABAZOV
2014H
 D0 $\mathit A_{FB}$ (${{\mathit \ell}}$ + $\not E_T$ + ${}\geq{}$3j (${}\geq{}1{{\mathit b}}$))
$20.1$ $\pm6.7$ 6
AALTONEN
2013AD
 CDF ${{\mathit a}_{{1}}}/{{\mathit a}_{{0}}}$ in ${{\mathit \ell}}+\not E_T+{}\geq{}$4j (${}\geq{}1{{\mathit b}}$)
$-0.2$ $\pm3.1$ 6
AALTONEN
2013AD
 CDF ${{\mathit a}_{{3}}},{{\mathit a}_{{5}}},{{\mathit a}_{{7}}}$ in ${{\mathit \ell}}+\not E_T+{}\geq{}$4j (${}\geq{}1{{\mathit b}}$)
$16.4$ $\pm4.7$ 7
AALTONEN
2013S
 CDF ${{\mathit \ell}}$ + $\not E_T$ +${}\geq{}$4 jets(${}\geq{}1{{\mathit b}}$-tag)
$9.4$ ${}^{+3.2}_{-2.9}$ 8
AALTONEN
2013X
 CDF ${{\mathit \ell}}$ + $\not E_T$ + ${}\geq{}$4 jets (${}\geq{}$1 ${{\mathit b}}$-tag)
$11.8$ $\pm3.2$ 9
ABAZOV
2013A
 D0 ${{\mathit \ell}}{{\mathit \ell}}$ $\&$ ${{\mathit \ell}}$+ jets comb.
$-11.6$ $\pm15.3$ 10
AALTONEN
2011F
 CDF ${\mathit m}_{\mathrm { {{\mathit t}} {{\overline{\mathit t}}} }}$ $<$ 450 GeV
$47.5$ $\pm11.4$ 10
AALTONEN
2011F
 CDF ${\mathit m}_{\mathrm { {{\mathit t}} {{\overline{\mathit t}}} }}$ $>$ 450 GeV
$19.6$ $\pm6.5$ 11
ABAZOV
2011AH
 D0 ${{\mathit \ell}}$ + $\not E_T$ +${}\geq{}$4 jets(${}\geq{}1{{\mathit b}}$-tag)
$17$ $\pm8$ 12
AALTONEN
2008AB
 CDF ${{\mathit p}}{{\overline{\mathit p}}}$ frame
$24$ $\pm14$ 12
AALTONEN
2008AB
 CDF ${{\mathit t}}{{\overline{\mathit t}}}$ frame
$12$ $\pm8$ $\pm1$ 13
ABAZOV
2008L
 D0 ${{\mathit \ell}}$ + $\not E_T$ + ${}\geq{}$4 jets
1  AALTONEN 2018 based on $9 - 10$ fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ data at $\sqrt {s }$ = 1.96 TeV. The value is the asymmetry in the number of reconstructed ${{\mathit t}}{{\overline{\mathit t}}}$ events with rapidity y$_{t}$ $>$ y$_{{{\overline{\mathit t}}}}$ and those with y$_{t}$ $<$ y$_{{{\overline{\mathit t}}}}$. The combined fits to CDF and D0 single lepton and ${{\mathit \ell}}{{\mathit \ell}}$ asymmetries give $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $0.073$ $\pm0.016$ $\pm0.012$ and $\mathit A{}^{ {{\mathit \ell}} {{\mathit \ell}} }_{FB}$ = $0.108$ $\pm0.043$ $\pm0.016$, respectively. The results are consistent with the SM predictions.
2  ABAZOV 2015K based on 9.7 fb${}^{-1}$ of data. The result is consistent with the SM predictions. By combining with the previous D0 measurement in the ${{\mathit \ell}}$ + jet channel ABAZOV 2014H, $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $0.118$ $\pm0.025$ $\pm0.013$ is obtained.
3  AALTONEN 2014F based on 9.1 fb${}^{-1}$ of data. $\mathit A{}^{{{\mathit \ell}}}_{FB}$ and $\mathit A{}^{{{\mathit \ell}}{{\mathit \ell}}}_{FB}$ denote, respectively, the asymmetries ($\mathit N(\mathit x>0)\text{-}\mathit N(\mathit x<0))/\mathit N_{tot}$ for $\mathit x$= ${{\mathit q}}$ $_{{{\mathit \ell}}}\eta _{{{\mathit \ell}}}$ ( ${{\mathit q}}$ $_{{{\mathit \ell}}}$ is the charge of ${{\mathit \ell}}$) and $\mathit x=\eta _{{{\mathit \ell}}{}^{+}}\text{-}\eta _{{{\mathit \ell}}{}^{-}}$. Both results are consistent with the SM predictions. By combining with the previous CDF measurement in the ${{\mathit \ell}}$+jet channel AALTONEN 2013X, $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $0.098$ ${}^{+0.028}_{-0.026}$ is obtained. The combined result is about two sigma larger than the SM prediction of $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $0.038$ $\pm0.003$.
4  Based on 9.7 fb${}^{-1}$ of ${{\mathit p}}{{\overline{\mathit p}}}$ data at $\sqrt {s }$ = 1.96 TeV. The asymmetry is corrected for the production level for events with $\vert $y$_{l}\vert $ $<$ 1.5. Asymmetry as functions of $\mathit E_{T}({{\mathit \ell}}$) and $\vert $y$_{l}\vert $ are given in Figs. 7 and 8, respectively. Combination with the asymmetry measured in the dilepton channel [ABAZOV 2013P] gives $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $4.2$ $\pm2.0$ $\pm1.4$ $\%$, in agreement with the SM prediction of 2.0$\%$.
5  Based on 9.7 fb${}^{-1}$ of data of ${{\mathit p}}{{\overline{\mathit p}}}$ data at $\sqrt {s }$=1.96 TeV. The measured asymmetry is in agreement with the SM predictions of $8.8$ $\pm0.9$ $\%$ [BERNREUTHER 2012 ], which includes the EW effects. The dependences of the asymmetry on $\vert $y(${{\mathit t}}$) $−$ y(${{\overline{\mathit t}}})\vert $ and ${\mathit m}_{ {{\mathit t}} {{\overline{\mathit t}}} }$ are shown in Figs. 9 and 10, respectively.
6  Based on 9.4 fb${}^{-1}$ of data. Reported $\mathit A_{FB}$ values come from the determination of ${{\mathit a}_{{i}}}$ coefficients of d$\sigma $/d(cos$\theta _{t}$) = $\Sigma _{i}{{\mathit a}_{{i}}}P_{i}$(cos($\theta _{t}$)) measurement. The result of ${{\mathit a}_{{1}}}/{{\mathit a}_{{0}}}$ = ($40$ $\pm12)\%$ seems higher than the NLO SM prediction of ($15$ ${}^{+7}_{-3})\%$.
7  Based on 9.4 fb${}^{-1}$ of data. The quoted result is the asymmetry at the parton level.
8  Based on 9.4 fb${}^{-1}$ of data. The observed asymmetry is to be compared with the SM prediction of $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $0.038$ $\pm0.003$.
9  Based on 5.4 fb${}^{-1}$ of data. ABAZOV 2013A studied the dilepton channel of the ${{\mathit t}}{{\overline{\mathit t}}}$ events and measured the leptonic forward-backward asymmetry to be $\mathit A{}^{{{\mathit \ell}}}_{FB}$ = $5.8$ $\pm5.1$ $\pm1.3\%$, which is consistent with the SM (QCD+EW) prediction of $4.7$ $\pm0.1\%$. The result is obtained after combining the measurement ($15.2$ $\pm4.0\%$) in the ${{\mathit \ell}}$ + jets channel ABAZOV 2011AH. The top quark helicity is measured by using the neutrino weighting method to be consistent with zero in both dilepton and ${{\mathit \ell}}$ + jets channels.
10  Based on 5.3 fb${}^{-1}$ of data. The error is statistical and systematic combined. Events with lepton + $\not E_T$ + ${}\geq{}$4jets(${}\geq{}1{{\mathit b}}$) are used. AALTONEN 2011F also measures the asymmetry as a function of the rapidity difference $\vert $y$_{t}$ $−$ y$_{{{\overline{\mathit t}}}}$ $\vert $. The NLO QCD predictions [MCFM] are ($4.0$ $\pm0.6)\%$ and ($8.8$ $\pm1.3)\%$ for ${\mathit m}_{\mathrm { {{\mathit t}} {{\overline{\mathit t}}} }}$ $<$ 450 and $>$ 450 GeV, respectively.
11  Based on 5.4 fb${}^{-1}$ of data. The error is statistical and systematic combined. The quoted asymmetry is obtained after unfolding to be compared with the MC@NLO prediction of ($5.0$ $\pm0.1)\%$. No significant difference between the ${\mathit m}_{\mathrm { {{\mathit t}} {{\overline{\mathit t}}} }}$ $<$ 450 and $>$ 450 GeV data samples is found. A corrected asymmetry based on the lepton from a top quark decay of ($15.2$ $\pm4.0)\%$ is measured to be compared to the MC@NLO prediction of ($2.1$ $\pm0.1)\%$.
12  Result is based on 1.9 fb${}^{-1}$ of data. The $\mathit FB$ asymmetry in the ${{\mathit t}}{{\overline{\mathit t}}}$ events has been measured in the ${{\mathit \ell}}$ + jets mode, where the lepton charge is used as the flavor tag. The asymmetry in the ${{\mathit p}}{{\overline{\mathit p}}}$ frame is defined in terms of cos $(\theta )$ of hadronically decaying ${{\mathit t}}$-quark momentum, whereas that in the ${{\mathit t}}{{\overline{\mathit t}}}$ frame is defined in terms of the ${{\mathit t}}$ and ${{\overline{\mathit t}}}$ rapidity difference. The results are consistent (${}\leq{}$ 2 $\sigma $) with the SM predictions.
13  Result is based on 0.9 fb${}^{-1}$ of data. The asymmetry in the number of ${{\mathit t}}{{\overline{\mathit t}}}$ events with y$_{t}$ $>$ y$_{{{\overline{\mathit t}}}}$ and those with y$_{t}$ $<$ y$_{{{\overline{\mathit t}}}}$ has been measured in the lepton + jets final state. The observed value is consistent with the SM prediction of 0.8$\%$ by MC@NLO, and an upper bound on the ${{\mathit Z}^{\,'}}$ $\rightarrow$ ${{\mathit t}}{{\overline{\mathit t}}}$ contribution for the SM ${{\mathit Z}}$-like couplings is given in in Fig. 2 for 350 GeV $<$ ${\mathit m}_{{{\mathit Z}^{\,'}}}$ $<$ 1 TeV.
References:
AALTONEN 2018
PRL 120 042001 Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron
ABAZOV 2015K
PR D92 052007 Simultaneous Measurement of Forward-Backward Asymmetry and Top Polarization in Dilepton Final States from ${\mathit {\mathit t}}{\mathit {\overline{\mathit t}}}$ Production at the Tevatron
AALTONEN 2014F
PRL 113 042001 Measurement of the Inclusive Leptonic Asymmetry in Top-Quark Pairs that Decay to Two Charged Leptons at CDF
Also
PRL 117 199901 (errat.) Erratum to AALTONEN 2014F: Measurement of the Inclusive Leptonic Asymmetry in Top-Quark Pairs that Decay to Two Charged Leptons at CDF
ABAZOV 2014H
PR D90 072011 Measurement of the Forward-Backward Asymmetry in Top Quark-Antiquark Production in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions using the Lepton + Jets Channel
ABAZOV 2014G
PR D90 072001 Measurement of the Forward-Backward Asymmetry in the Distribution of Leptons in ${\mathit {\mathit t}}{\mathit {\overline{\mathit t}}}$ Events in the Lepton $+$ Jets Channel
AALTONEN 2013S
PR D87 092002 Measurement of the Top Quark Forward-Backward Production Asymmetry and its Dependence on Event Kinematic Properties
AALTONEN 2013AD
PRL 111 182002 Measurement of the Differential Cross Section $\mathit d\sigma /\mathit d$(cos $\mathit \theta _{t}$) for Top-Quark Pair Production in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV
AALTONEN 2013X
PR D88 072003 Measurement of the Leptonic Asymmetry in ${\mathit {\mathit t}}{\mathit {\overline{\mathit t}}}$ Events Produced in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV
ABAZOV 2013A
PR D87 011103 Measurement of Leptonic Asymmetries and Top Quark Polarization in ${\mathit {\mathit t}}{\mathit {\overline{\mathit t}}}$ Production
AALTONEN 2011F
PR D83 112003 Evidence for a Mass Dependent Forward-Backward Asymmetry in Top Quark Pair Production
ABAZOV 2011AH
PR D84 112005 Forward-Backward Asymmetry in Top Quark-Antiquark Production
AALTONEN 2008AB
PRL 101 202001 Forward-Backward Asymmetry in Top Quark Production in ${{\mathit p}}{{\overline{\mathit p}}}$ Collisions at $\sqrt {s }$ = 1.96 TeV
ABAZOV 2008L
PRL 100 142002 First Measurement of the Forward-Backward Charge Asymmetry in Top-Quark Pair Production