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Weak Neutral Currents in e+ e- Collisions at s**(1/2)=29-GeV

Levi, M.E. ; Blocker, C.A. ; Strait, J. ; et al.
Phys.Rev.Lett. 51 (1983) 1941, 1983.
Inspire Record 191845 DOI 10.17182/hepdata.3281
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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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Study of fermion pair production in $e^{+} e^{-}$ collisions at 130-GeV to 183-GeV

The ALEPH collaboration Barate, R. ; Decamp, D. ; Ghez, Philippe ; et al.
Eur.Phys.J. C12 (2000) 183-207, 2000.
Inspire Record 498072 DOI 10.17182/hepdata.49128

The cross sections and forward-backward asymmetries of hadronic and leptonic events produced in e+e- collisions at centre-of-mass energies of 130-183 GeV are presented. Results for ee, mumu, tautau, qq, bb and cc production show no significant deviation from the Standard Model predictions. This enable constraints to be set upon physics beyond the Standard Model such as four-fermion contact interactions, leptoquarks, Z' bosons and R-parity violating squarks and sneutrinos. Limits on the energy scale Lambda of eeff contact interactions are typically in the range from 2-10 TeV. Limits on R-parity violating sneutrinos reach masses of a few hundred GeV for large values of their Yukawa couplings.

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Study of Z boson production in pPb collisions at $\sqrt {s NN }$=5.02TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B759 (2016) 36-57, 2016.
Inspire Record 1410832 DOI 10.17182/hepdata.71358
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Measurement of forward W and Z boson production in $pp$ collisions at $ \sqrt{s}=8 $ TeV

The LHCb collaboration Aaij, Roel ; Abellán Beteta, Carlos ; Adeva, Bernardo ; et al.
JHEP 1601 (2016) 155, 2016.
Inspire Record 1406555 DOI 10.17182/hepdata.71419

Measurements are presented of electroweak boson production using data from pp collisions at a centre-of-mass energy of $ \sqrt{s}=8 $ TeV. The analysis is based on an integrated luminosity of 2.0 fb$^{−1}$ recorded with the LHCb detector. The bosons are identified in the W → μν and Z → μ$^{+}$ μ$^{−}$ decay channels. The cross-sections are measured for muons in the pseudorapidity range 2.0 < η < 4.5, with transverse momenta p$_{T}$ > 20 GeV/c and, in the case of the Z boson, a dimuon mass within $ 60 < {M}_{\mu }{{{}_{{}^{+}}}_{\mu}}_{{}^{-}}<120 $ GeV/c$^{2}$. The results are $ {\sigma}_W{{}_{{}^{+}}}_{\to \mu }{{}_{{}^{+}}}_{\nu }=1093.6\pm 2.1\pm 7.2\pm 10.9\pm 12.7\ \mathrm{p}\mathrm{b}, $ $ {\sigma}_W{{}_{{}^{-}}}_{\to \mu }{{}_{{}^{-}}}_{\overline{\nu}}=818.4\pm 1.9\pm 5.0\pm 7.0\pm 9.5\ \mathrm{p}\mathrm{b}, $ $ {\sigma}_{\mathrm{Z}\to \mu }{{{}_{{}^{+}}}_{\mu}}_{{}^{-}}=95.0\pm 0.3\pm 0.7\pm 1.1\pm 1.1\ \mathrm{p}\mathrm{b}, $ $ {\sigma}_{Z\to \mu }{{{}_{{}^{+}}}_{\mu}}_{{}^{-}}=95.0\pm 0.3\pm 0.7\pm 1.1\pm 1.1\ \mathrm{p}\mathrm{b}, $ where the first uncertainties are statistical, the second are systematic, the third are due to the knowledge of the LHC beam energy and the fourth are due to the luminosity determination. The evolution of the W and Z boson cross-sections with centre-of-mass energy is studied using previously reported measurements with 1.0 fb$^{−1}$ of data at 7 TeV. Differential distributions are also presented. Results are in good agreement with theoretical predictions at next-to-next-to-leading order in perturbative quantum chromodynamics.

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Electroweak studies in e+ e- collisions: 12 < s**(1/2) < 46.78 GeV

The MARK J collaboration Adeva, B. ; Anderhub, H. ; Ansari, S. ; et al.
Phys.Rev. D38 (1988) 2665-2678, 1988.
Inspire Record 274887 DOI 10.17182/hepdata.23272
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Measurement of longitudinal spin asymmetries for weak boson production in polarized proton-proton collisions at RHIC

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.Lett. 113 (2014) 072301, 2014.
Inspire Record 1292792 DOI 10.17182/hepdata.73441

We report measurements of single- and double- spin asymmetries for $W^{\pm}$ and $Z/\gamma^*$ boson production in longitudinally polarized $p+p$ collisions at $\sqrt{s} = 510$ GeV by the STAR experiment at RHIC. The asymmetries for $W^{\pm}$ were measured as a function of the decay lepton pseudorapidity, which provides a theoretically clean probe of the proton's polarized quark distributions at the scale of the $W$ mass. The results are compared to theoretical predictions, constrained by recent polarized deep inelastic scattering measurements, and show a preference for a sizable, positive up antiquark polarization in the range $0.05<x<0.2$.

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Measurement of $D_s^{\pm}$ production asymmetry in $pp$ collisions at $\sqrt{s} =7$ and 8 TeV

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1808 (2018) 008, 2018.
Inspire Record 1674916 DOI 10.17182/hepdata.82715

The inclusive D$_{s}^{±}$ production asymmetry is measured in pp collisions collected by the LHCb experiment at centre-of-mass energies of $ \sqrt{s}=7 $ and 8 TeV. Promptly produced D$_{s}^{±}$ mesons are used, which decay as D$_{s}^{±}$  → ϕπ$^{±}$, with ϕ → K$^{+}$K$^{−}$. The measurement is performed in bins of transverse momentum, p$_{T}$, and rapidity, y, covering the range 2.5 < p$_{T}$ < 25.0 GeV/c and 2.0 < y < 4.5. No kinematic dependence is observed. Evidence of nonzero D$_{s}^{±}$ production asymmetry is found with a significance of 3.3 standard deviations.

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Measurement of the forward-backward asymmetry in top quark-antiquark production in ppbar collisions using the lepton+jets channel

The D0 collaboration Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; Acharya, Bannanje Sripath ; et al.
Phys.Rev. D90 (2014) 072011, 2014.
Inspire Record 1293918 DOI 10.17182/hepdata.64123
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Angular analysis of the decay $B^0 \to K^{*0} \mu^+ \mu^-$ from pp collisions at $\sqrt s = 8$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B753 (2016) 424-448, 2016.
Inspire Record 1385600 DOI 10.17182/hepdata.17057
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First measurement of the left-right cross-section asymmetry in Z boson production by e+ e- collisions

The SLD collaboration Abe, K. ; Abt, I. ; Acton, P.D. ; et al.
Phys.Rev.Lett. 70 (1993) 2515-2520, 1993.
Inspire Record 352667 DOI 10.17182/hepdata.19765
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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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Charged particle nuclear modification factor and pseudorapidity asymmetry in pPb collisions at sqrt(sNN)=5.02 TeV with CMS

The CMS collaboration
No Journal Information, None.
Inspire Record 1263706 DOI 10.17182/hepdata.66742

The charged particle transverse momentum spectra in the midrapidity and forward pseudorapidity ranges are presented for pPb collisions at $\sqrt{s_{\rm NN}}=5.02$~TeV. The data sample corresponding to an integrated luminosity of 26~${\rm nb}^{-1}$ was collected with the CMS detector at the LHC. The nuclear modification factor is measured at midrapidity by normalizing the measured pPb spectrum to a pp reference spectrum constructed from previous measurements. In addition, the asymmetries in the charged particle yields between equivalent positive and negative pseudorapidity ranges in the center-of-mass frame are presented as a function of transverse momentum.

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Measurement of the electron charge asymmetry in inclusive $W$ production in $pp$ collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 109 (2012) 111806, 2012.
Inspire Record 1118047 DOI 10.17182/hepdata.66333

A measurement of the electron charge asymmetry in inclusive pp to W + X to e nu + X production at sqrt(s) = 7 TeV is presented based on data recorded by the CMS detector at the LHC and corresponding to an integrated luminosity of 840 inverse picobarns. The electron charge asymmetry reflects the unequal production of positive and negative W bosons in pp collisions. The electron charge asymmetry is measured in bins of absolute value of electron pseudorapidity in the range of abs(eta) < 2.4. The asymmetry rises from about 0.1 to 0.2 as a function of the pseudorapidity and is measured with a relative precision better than 7%. This measurement provides new stringent constraints for parton distribution functions.

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Inclusive and differential measurements of the $t\overline{t}$ charge asymmetry in pp collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B757 (2016) 154-179, 2016.
Inspire Record 1382590 DOI 10.17182/hepdata.68759
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Measurement of the forward $W$ boson cross-section in $pp$ collisions at $\sqrt{s} = 7 {\rm \, TeV}$

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1412 (2014) 079, 2014.
Inspire Record 1311488 DOI 10.17182/hepdata.11760
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Measurement of the forward $Z$ boson production cross-section in $pp$ collisions at $\sqrt{s}=7$ TeV

The LHCb collaboration Aaij, Roel ; Adeva, Bernardo ; Adinolfi, Marco ; et al.
JHEP 1508 (2015) 039, 2015.
Inspire Record 1373300 DOI 10.17182/hepdata.2114

A measurement of the production cross-section for Z bosons that decay to muons is presented. The data were recorded by the LHCb detector during pp collisions at a centre-of-mass energy of 7 TeV, and correspond to an integrated luminosity of 1.0 fb$^{−1}$. The cross-section is measured for muons in the pseudorapidity range 2.0 < η < 4.5 with transverse momenta p$_{T}$ > 20 GeV/c. The dimuon mass is restricted to 60 < M$_{μ}$ +$_{μ}$ − < 120 GeV/c$^{2}$. The measured cross-section is $ {\sigma}_{Z\to \mu }{+}_{\mu }-=\left(76.0\pm 0.3\pm 0.5\pm 1.0\pm 1.3\right)\mathrm{p}\mathrm{b} $

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Spin correlation in $t\bar{t}$ production from $p\bar{p}$ collisions at $\sqrt{s} = 1.8$ TeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 85 (2000) 256-261, 2000.
Inspire Record 524260 DOI 10.17182/hepdata.42996

The D0 collaboration has performed a study of spin correlation in tt-bar production for the process tt-bar to bb-bar W^+W^-, where the W bosons decay to e-nu or mu-nu. A sample of six events was collected during an exposure of the D0 detector to an integrated luminosity of approximately 125 pb^-1 of sqrt{s}=1.8 TeV pp-bar collisions. The standard model (SM) predicts that the short lifetime of the top quark ensures the transmission of any spin information at production to the tt-bar decay products. The degree of spin correlation is characterized by a correlation coefficient k. We find that k>-0.25 at the 68% confidence level, in agreement with the SM prediction of k=0.88.

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Precise measurement of the left-right cross-section asymmetry in Z boson production by e+ e- collisions

The SLD collaboration Abe, K. ; Abt, I. ; Ash, W.W. ; et al.
Phys.Rev.Lett. 73 (1994) 25-29, 1994.
Inspire Record 373007 DOI 10.17182/hepdata.19681

We present a precise measurement of the left-right cross section asymmetry ($A_{LR}$) for $Z$ boson production by $\ee$ collisions. The measurement was performed at a center-of-mass energy of 91.26 GeV with the SLD detector at the SLAC Linear Collider (SLC). The luminosity-weighted average polarization of the SLC electron beam was (63.0$\pm$1.1)%. Using a sample of 49,392 $\z0$ decays, we measure $A_{LR}$ to be 0.1628$\pm$0.0071(stat.)$\pm$0.0028(syst.) which determines the effective weak mixing angle to be $\swein=0.2292\pm0.0009({\rm stat.})\pm0.0004({\rm syst.})$.}

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Precise measurement of the left-right cross-section asymmetry in Z boson production by e+ e- collisions

The SLD collaboration Schumm, B.A. ;
Nucl.Phys.Proc.Suppl. 40 (1995) 497-503, 1995.
Inspire Record 389176 DOI 10.17182/hepdata.31853
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Charged-pion cross sections and double-helicity asymmetries in polarized p+p collisions at $\sqrt{s}$=200  GeV

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev. D91 (2015) 032001, 2015.
Inspire Record 1315330 DOI 10.17182/hepdata.71403

We present the midrapidity charged pion invariant cross sections and the ratio of $\pi^-$-to-$\pi^+$ production ($5<p_T<13$ GeV/$c$), together with the double-helicity asymmetries ($5<p_T<12$ GeV/$c$) in polarized $p$$+$$p$ collisions at $\sqrt{s} = 200$ GeV. The cross section measurements are consistent with perturbative calculations in quantum chromodynamics within large uncertainties in the calculation due to the choice of factorization, renormalization, and fragmentation scales. However, the theoretical calculation of the ratio of $\pi^-$-to-$\pi^+$ production when considering these scale uncertainties overestimates the measured value, suggesting further investigation of the uncertainties on the charge-separated pion fragmentation functions is needed. Due to cancellations of uncertainties in the charge ratio, direct inclusion of these ratio data in future parameterizations should improve constraints on the flavor dependence of quark fragmentation functions to pions. By measuring charge-separated pion asymmetries, one can gain sensitivity to the sign of $\Delta G$ through the opposite sign of the up and down quark helicity distributions in conjunction with preferential fragmentation of positive pions from up quarks and negative pions from down quarks. The double-helicity asymmetries presented are sensitive to the gluon helicity distribution over an $x$ range of $\sim$0.03--0.16.

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Forward–backward asymmetry of Drell–Yan lepton pairs in pp collisions at $\sqrt{s} = 8$ $\,\mathrm{TeV}$

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Eur.Phys.J. C76 (2016) 325, 2016.
Inspire Record 1415949 DOI 10.17182/hepdata.73121

A measurement of the forward–backward asymmetry ${A}_{\mathrm{FB}}$ of oppositely charged lepton pairs ( $\mu \mu $ and $\mathrm{e}\mathrm{e}$ ) produced via $\mathrm{Z}/\gamma ^*$ boson exchange in pp collisions at $\sqrt{s} = 8$ $\,\mathrm{TeV}$ is presented. The data sample corresponds to an integrated luminosity of 19.7 $\,\mathrm{fb}^{-1}$ collected with the CMS detector at the LHC. The measurement of ${A}_{\mathrm{FB}}$ is performed for dilepton masses between 40 $\,\text {GeV}$ and 2 $\,\mathrm{TeV}$ and for dilepton rapidity up to 5. The ${A}_{\mathrm{FB}}$ measurements as a function of dilepton mass and rapidity are compared with the standard model predictions.

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Measurement of parity-violating spin asymmetries in W$^{\pm}$ production at midrapidity in longitudinally polarized $p$$+$$p$ collisions

The PHENIX collaboration Adare, A. ; Aidala, C. ; Ajitanand, N.N. ; et al.
Phys.Rev. D93 (2016) 051103, 2016.
Inspire Record 1365091 DOI 10.17182/hepdata.73691

We present midrapidity measurements from the PHENIX experiment of large parity-violating single-spin asymmetries of high transverse momentum electrons and positrons from W±/Z decays, produced in longitudinally polarized p+p collisions at center of mass energies of s=500 and 510 GeV. These asymmetries allow direct access to the antiquark polarized parton distribution functions due to the parity-violating nature of the W-boson coupling to quarks and antiquarks. The results presented are based on data collected in 2011, 2012, and 2013 with an integrated luminosity of 240  pb-1, which exceeds previous PHENIX published results by a factor of more than 27. These high Q2 data probe the parton structure of the proton at W mass scale and provide an important addition to our understanding of the antiquark parton helicity distribution functions at an intermediate Bjorken x value of roughly MW/s=0.16.

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Measurement of the forward-backward asymmetry of $\Lambda$ and $\bar{\Lambda}$ production in $p \bar{p}$ collisions

The D0 collaboration Abazov, Victor Mukhamedovich ; Abbott, Braden Keim ; Acharya, Bannanje Sripath ; et al.
Phys.Rev. D93 (2016) 032002, 2016.
Inspire Record 1404885 DOI 10.17182/hepdata.76972

We study $\Lambda$ and $\bar{\Lambda}$ production asymmetries in $p \bar{p} \rightarrow \Lambda (\bar{\Lambda}) X$, $p \bar{p} \rightarrow J/\psi \Lambda (\bar{\Lambda}) X$, and $p \bar{p} \rightarrow \mu^\pm \Lambda (\bar{\Lambda}) X$ events recorded by the D0 detector at the Fermilab Tevatron collider at $\sqrt{s} = 1.96$ TeV. We find an excess of $\Lambda$'s ($\bar{\Lambda}$'s) produced in the proton (antiproton) direction. This forward-backward asymmetry is measured as a function of rapidity. We confirm that the $\bar{\Lambda}/\Lambda$ production ratio, measured by several experiments with various targets and a wide range of energies, is a universal function of "rapidity loss", i.e., the rapidity difference of the beam proton and the lambda.

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Observation of charge asymmetry dependence of pion elliptic flow and the possible chiral magnetic wave in heavy-ion collisions

The STAR collaboration Adamczyk, L. ; Adkins, J.K. ; Agakishiev, G. ; et al.
Phys.Rev.Lett. 114 (2015) 252302, 2015.
Inspire Record 1358666 DOI 10.17182/hepdata.72237

We present measurements of π- and π+ elliptic flow, v2, at midrapidity in Au+Au collisions at sNN=200, 62.4, 39, 27, 19.6, 11.5, and 7.7 GeV, as a function of event-by-event charge asymmetry, Ach, based on data from the STAR experiment at RHIC. We find that π- (π+) elliptic flow linearly increases (decreases) with charge asymmetry for most centrality bins at sNN=27  GeV and higher. At sNN=200  GeV, the slope of the difference of v2 between π- and π+ as a function of Ach exhibits a centrality dependence, which is qualitatively similar to calculations that incorporate a chiral magnetic wave effect. Similar centrality dependence is also observed at lower energies.

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