Measurement of the charge asymmetry in highly boosted top-quark pair production in $\sqrt{s} =$ 8 TeV $pp$ collision data collected by the ATLAS experiment

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett. B756 (2016) 52-71, 2016.
Inspire Record 1410588 DOI 10.17182/hepdata.77021

In the pp→tt¯ process the angular distributions of top and anti-top quarks are expected to present a subtle difference, which could be enhanced by processes not included in the Standard Model. This Letter presents a measurement of the charge asymmetry in events where the top-quark pair is produced with a large invariant mass. The analysis is performed on 20.3 fb −1 of pp collision data at s=8TeV collected by the ATLAS experiment at the LHC, using reconstruction techniques specifically designed for the decay topology of highly boosted top quarks. The charge asymmetry in a fiducial region with large invariant mass of the top-quark pair ( mtt¯>0.75 TeV ) and an absolute rapidity difference of the top and anti-top quark candidates within −2<|yt|−|yt¯|<2 is measured to be 4.2±3.2% , in agreement with the Standard Model prediction at next-to-leading order. A differential measurement in three tt¯ mass bins is also presented.

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The Forward - backward asymmetry for charm quarks at the Z

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Lett. B434 (1998) 415-425, 1998.
Inspire Record 472954 DOI 10.17182/hepdata.49353

The data set collected with the ALEPH detector from 1991 to 1995 at LEP has been analysed to measure the charm forward-backward asymmetry at the Z. Out of a total of 4.1 million hadronic Z decays, about 36000 high momentum D*+, D+ and D0 decays were reconstructed, of which 80% originate from Z -> ccbar events...

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Determination of A-b(FB) using jet charge measurements in Z decays

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Lett. B426 (1998) 217-230, 1998.
Inspire Record 468671 DOI 10.17182/hepdata.49559
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Study of the muon pair production at center-of-mass energies from 20-GeV to 136-GeV with the ALEPH detector

The ALEPH collaboration Barate, R. ; Buskulic, D. ; Decamp, D. ; et al.
Phys.Lett. B399 (1997) 329-341, 1997.
Inspire Record 440218 DOI 10.17182/hepdata.47490
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Measurement of hadron and lepton pair production from $e^{+} e^{-}$ annihilation at center-of-mass energies of 130-GeV and 136-GeV

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Phys.Lett. B378 (1996) 373-384, 1996.
Inspire Record 421552 DOI 10.17182/hepdata.47801
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Measurement of Lambda polarization from Z decays

The ALEPH collaboration Buskulic, D. ; De Bonis, I. ; Decamp, D. ; et al.
Phys.Lett. B374 (1996) 319-330, 1996.
Inspire Record 415745 DOI 10.17182/hepdata.47830
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Measurement of the forward backward asymmetry of c and b quarks at the Z pole using reconstructed D mesons

The DELPHI collaboration Abreu, P. ; Adye, T. ; Adzic, P. ; et al.
Eur.Phys.J. C10 (1999) 219-237, 1999.
Inspire Record 495464 DOI 10.17182/hepdata.49295

A measurement of the forward--backward asymmetry of $e^{+}e^{-} \to c\bar{c}$ and $e^{+}e^{-} \to b\bar{b}$ on the $Z$ resonance is performed using about 3.5 million hadronic $Z$ decays collected by the DELPHI detector at LEP in the years 1992 to 1995. The heavy quark is tagged by the exclusive reconstruction of several $D$ meson decay modes. The forward--backward asymmetries for $c$ and $b$ quarks at the $Z$ resonance are determined to be: \[ \renewcommand{\arraystretch}{1.6} \begin{array}{rcr@{}l} \Afbc(\sqrt{s} = 91.235 {\rm GeV}) &=& &0.0659 \pm 0.0094 (stat) \pm 0.0035 (syst) \Afbb (\sqrt{s} = 91.235 {\rm GeV}) &=& &0.0762 \pm 0.0194 (stat) \pm 0.0085 (syst) \Afbc(\sqrt{s} = 89.434 {\rm GeV}) &=&-&0.0496 \pm 0.0368 (stat) \pm 0.0053 (syst) \Afbb(\sqrt{s} = 89.434 {\rm GeV}) &=& &0.0567 \pm 0.0756 (stat) \pm 0.0117 (syst) \Afbc(\sqrt{s} = 92.990 {\rm GeV}) &=& &0.1180 \pm 0.0318 (stat) \pm 0.0062 (syst) \Afbb(\sqrt{s} = 92.990 {\rm GeV}) &=& &0.0882 \pm 0.0633 (stat) \pm 0.0122 (syst) \end{array} \] The combination of these results leads to an effective electroweak mixing angle of: SINEFF = 0.2332 \pm 0.0016

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A Measurement of the $e^+ e^- \to b \bar{b}$ Forward - Backward Charge Asymmetry at $\sqrt{s}=29$-{GeV}

The MAC collaboration Band, H. ; Camporesi, T. ; Chadwick, G.B. ; et al.
Phys.Lett. B218 (1989) 369-373, 1989.
Inspire Record 276692 DOI 10.17182/hepdata.29845
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Energy Dependence of the Charge Asymmetry a ($T (\pi$), $\theta$) in $\pi d$ Elastic Scattering

Smith, G.R. ; Gill, D.R. ; Ottewell, D. ; et al.
Phys.Rev. C38 (1988) 240-250, 1988.
Inspire Record 250814 DOI 10.17182/hepdata.26223
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Measurement of $K^0_{S}$, $\Lambda$, $\bar{\Lambda}$ production at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J. C51 (2007) 1-23, 2007.
Inspire Record 734144 DOI 10.17182/hepdata.45796

The production of the neutral strange hadrons $K^{0}_{S}$, $\Lambda$ and $\bar{\Lambda}$ has been measured in $ep$ collisions at HERA using the ZEUS detector. Cross sections, baryon-to-meson ratios, relative yields of strange and charged light hadrons, $\Lambda$ ($\bar{\Lambda}$) asymmetry and polarization have been measured in three kinematic regions: $Q^2 > 25 \gev^2$: $5 < Q^2 < 25 \gev^2$: and in photoproduction ($Q^2 \simeq 0$). In photoproduction the presence of two hadronic jets, each with at least $5 \gev$ transverse energy, was required. The measurements agree in general with Monte Carlo models and are consistent with measurements made at $e^+ e^-$ colliders, except for an enhancement of baryon relative to meson production in photoproduction.

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Measurement of the electron charge asymmetry in $p \bar{p} \to W + X \to e \nu + X$ events at $\sqrt{s}$ = 1.96-TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 101 (2008) 211801, 2008.
Inspire Record 791230 DOI 10.17182/hepdata.42683

We present a measurement of the electron charge asymmetry in ppbar->W+X->enu+X events at a center of mass energy of 1.96 TeV using 0.75 fb-1 of data collected with the D0 detector at the Fermilab Tevatron Collider. The asymmetry is measured as a function of the electron transverse momentum and pseudorapidity in the interval (-3.2, 3.2) and is compared with expectations from next-to-leading order calculations in perturbative quantum chromodynamics. These measurements will allow more accurate determinations of the proton parton distribution functions.

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Asymmetries in the production of Lambda0, Xi-, and Omega- hyperons in 500-GeV/c pi minus: Nucleon interactions

The E791 collaboration Aitala, E.M. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Lett. B496 (2000) 9-18, 2000.
Inspire Record 532973 DOI 10.17182/hepdata.42997

Using data from Fermilab fixed-target experiment E791, we have measured particle-antiparticle production asymmetries for lambda zero, cascade minus, and omega minus hyperons in pi minus-nucleon interactions at 500 GeV/c. The asymmetries are measured as functions of Feynman-x (x_F) and pt^2 over the ranges of -0.12 GE x_F LE 0.12 and 0 GE pt^2 LE 4 (GeV/c)^2. We find substantial asymmetries, even at x_F = 0. We also observe leading-particle- type asymmetries which qualitatively agree with theoretical predictions.

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Measurement of the angular distribution of electrons from $W \to e \nu$ decays observed in $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev. D63 (2001) 072001, 2001.
Inspire Record 533572 DOI 10.17182/hepdata.41717

We present the first measurement of the electron angular distribution parameter alpha_2 in W to e nu events produced in proton-antiproton collisions as a function of the W boson transverse momentum. Our analysis is based on data collected using the D0 detector during the 1994--1995 Fermilab Tevatron run. We compare our results with next-to-leading order perturbative QCD, which predicts an angular distribution of (1 +/- alpha_1 cos theta* + alpha_2 cos^2 theta*), where theta* is the polar angle of the electron in the Collins-Soper frame. In the presence of QCD corrections, the parameters alpha_1 and alpha_2 become functions of p_T^W, the W boson transverse momentum. This measurement provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W boson mass measurement.

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Enhanced leading production of D+- and D*+- in 250-GeV pi+- - nucleon interactions

The E769 collaboration Alves, G.A. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Rev.Lett. 72 (1994) 812-815, 1994.
Inspire Record 361344 DOI 10.17182/hepdata.42499
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Measurement of the left-right forward - backward asymmetry for charm quarks with D*+ and D+ mesons

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Phys.Rev.Lett. 75 (1995) 3609-3613, 1995.
Inspire Record 404272 DOI 10.17182/hepdata.19646
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Forward - backward charge asymmetry of quark pairs produced at the KEK TRISTAN e+ e- collider

The AMY collaboration Stuart, D. ; Breedon, R.E. ; Chinitz, L.M. ; et al.
Phys.Rev. D49 (1994) 3098-3105, 1994.
Inspire Record 378569 DOI 10.17182/hepdata.22552
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Inclusive Electron Production From Heavy Quarks in $e^+ e^-$ Annihilation at 34.6-{GeV} Center-of-mass Energy

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Phys.Lett. B146 (1984) 443-449, 1984.
Inspire Record 202782 DOI 10.17182/hepdata.30507

The production of electrons by bottom and charm hadrons has been studied in e + e − annihilation at 34.6 GeV center of mass energy. It is observed that the b quark fragmentation function is peaked at large values of the scaling variable z with 〈 z b 〉 = 0.84 +0.15 + 0.15 −0.10 − 0.11 . For c quarks 〈 z c 〉 = 0.57 +0.10 + 0.05 −0.09 − 0.06 is observed. A forward-backward charge asymmetry of A = −0.25 ± 0.22 was measured in b production.

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Polarization at Small Angles in Anti-proton - Carbon Elastic Scattering at {LEAR} Energies

The SING collaboration Martin, A. ; Birsa, R. ; Bos, K. ; et al.
Nucl.Phys. A487 (1988) 563-590, 1988.
Inspire Record 261245 DOI 10.17182/hepdata.37001
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A Measurement of the Charmed Quark Asymmetry in $e^+ e^-$ Annihilation

The JADE collaboration Ould-Saada, F. ; Allison, John ; Ambrus, K. ; et al.
Z.Phys. C44 (1989) 567, 1989.
Inspire Record 278937 DOI 10.17182/hepdata.15357
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Measurement of the polarized forward - backward asymmetry of Z0 ---> b anti-b using a lifetime tag and momentum weighted track charge

The SLD collaboration Abe, K. ; Abt, I. ; Ahn, C.J. ; et al.
Conference Paper, 1995.
Inspire Record 398301 DOI 10.17182/hepdata.18618
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A Measurement of the Weak Axial Couplings of the $b$ and $c$ Quark

The JADE collaboration Elsen, E. ; Allison, John ; Ambrus, K. ; et al.
Z.Phys. C46 (1990) 349-360, 1990.
Inspire Record 282535 DOI 10.17182/hepdata.15241
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Heavy Quark Charge Asymmetries With the Cello Detector

The CELLO collaboration Behrend, H.J. ; Criegee, L. ; Field, J.H. ; et al.
Z.Phys. C47 (1990) 333-342, 1990.
Inspire Record 282536 DOI 10.17182/hepdata.15243
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Forward - backward charge asymmetry in $e^+e^- \to$ hadron jets

The AMY collaboration Stuart, D. ; Breedon, R.E. ; Kim, G.N. ; et al.
Phys.Rev.Lett. 64 (1990) 983, 1990.
Inspire Record 283082 DOI 10.17182/hepdata.19965
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Production and Muonic Decay of Heavy Quarks in e+ e- Annihilation at 34.5-GeV

The TASSO collaboration Althoff, M. ; Braunschweig, W. ; Kirschfink, F.J. ; et al.
Z.Phys. C22 (1984) 219, 1984.
Inspire Record 194775 DOI 10.17182/hepdata.16252

The production of prompt muons ine+e− annihilation has been studied at centre of mass energies near 34.5 GeV. The measured semi-muonic branching ratios ofb andc quarks areB(b»Xμv) =0.117±0.028±0.01 andB(c→Xμv)=0.082 ±0.012a−0.01+0.02. The fragmentation functions of heavy quarks are hard, <zb>=0.85a−0.12–0.07+0.10+0.02 and <zc> =0.77a−0.07–0.11+0.05+0.03. Limits have been set on flavour changing neutral current decays:B(b→Xµ+µ−) <0.02 andB(b→Xµ+µ− (95% confidence level).

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Asymmetries in the production of Lambda(c)+ and Lambda(c)- baryons in 500-GeV/c pi- nucleon interactions

The E791 collaboration Aitala, E.M. ; Amato, S. ; Anjos, J.C. ; et al.
Phys.Lett. B495 (2000) 42-48, 2000.
Inspire Record 531814 DOI 10.17182/hepdata.50150

We present a measurement of asymmetries in the production of $\Lambda_c^+$ and $\Lambda_c^-$ baryons in 500 GeV/c $\pi^-$--nucleon interactions from the E791 experiment at Fermilab. The asymmetries were measured as functions of Feynman x ($x_F$) and transverse momentum squared ($p_T^2$) using a sample of $1819 \pm 62$ $\Lambda_c$'s observed in the decay channel $\Lambda_c \to pK^-\pi^+$. We observe more $\Lambda_c^+$ than $\Lambda_c^-$ baryons, with an asymmetry of $(12.7\pm3.4\pm1.3) %$ independent of $x_F$ and $p_T^2$ in our kinematical range $(-0.1 < x_F < 0.6$ and $0.0 < p_T^2 < 8.0 (GeV/c)^2$). This $\Lambda_c$ asymmetry measurement is the first with data in both the positive and negative $x_F$ regions.

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