Measurement of the electron charge asymmetry in p anti-p ---> W + X ---> e nu + X events at s**(1/2) = 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.

1 data table match query

Folded electron charged asymmetry.


Measurement of the forward-backward asymmetry of electron and muon pair-production in $pp$ collisions at $\sqrt{s}$ = 7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 09 (2015) 049, 2015.
Inspire Record 1351916 DOI 10.17182/hepdata.76996

This paper presents measurements from the ATLAS experiment of the forward-backward asymmetry in the reaction $pp\rightarrow Z/\gamma^{*}\rightarrow l^{+}l^{-}$, with $l$ being electrons or muons, and the extraction of the effective weak mixing angle. The results are based on the full set of data collected in 2011 in $pp$ collisions at the LHC at $\sqrt{s}$ = 7 TeV, corresponding to an integrated luminosity of 4.8 fb$^{-1}$. The measured asymmetry values are found to be in agreement with the corresponding Standard Model predictions. The combination of the muon and electron channels yields a value of the effective weak mixing angle of $0.2308 \pm 0.0005 \mathrm{(stat.)} \pm 0.0006 \mathrm{(syst.)} \pm 0.0009\mathrm{(PDF)}$, where the first uncertainty corresponds to data statistics,the second to systematic effects and the third to knowledge of the parton density functions. This result agrees with the current world average from the Particle Data Group fit.

4 data tables match query

Summary of central values and total systematical uncertainties for the $A_{FB}$ values unfolded for mass bin migration and dilution effects in the CC electron channel, CF electron channel and muon channel.

Summary of central values and total systematical uncertainties for the unfolded $A_{FB}$ values which takes into account mass bin migration only in CC electron channel for Born and Dressed leptons. Dressed leptons are constructed by adding 4-vectors of the bare lepton and all real photons coming from the boson/lepton decay within a $\Delta R<$0.1.

Summary of central values and total systematical uncertainties for the unfolded $A_{FB}$ values which takes into account mass bin migration only in CF electron channel for Born and Dressed leptons. Dressed leptons are constructed by adding 4-vectors of the bare lepton and all real photons coming from the boson/lepton decay within a $\Delta R<$0.1.

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Measurement of high-Q2 neutral current deep inelastic e+p scattering cross sections with a longitudinally polarised positron beam at HERA

The ZEUS collaboration Abramowicz, H. ; Abt, I. ; Adamczyk, L. ; et al.
Phys.Rev.D 87 (2013) 052014, 2013.
Inspire Record 1183813 DOI 10.17182/hepdata.62614

Measurements of neutral current cross sections for deep inelastic scattering in e+p collisions at HERA with a longitudinally polarised positron beam are presented. The single-differential cross-sections d(sigma)/dQ2, d(sigma)/dx and d(sigma)/dy and the reduced cross-section were measured in the kinematic region Q2 > 185 GeV2 and y < 0.9, where Q2 is the four-momentum transfer squared, x the Bjorken scaling variable, and y the inelasticity of the interaction. The measurements were performed separately for positively and negatively polarised positron beams. The measurements are based on an integrated luminosity of 135.5 pb-1 collected with the ZEUS detector in 2006 and 2007 at a centre-of-mass energy of 318 GeV. The structure functions F3 and F3(gamma)Z were determined by combining the e+p results presented in this paper with previously published e-p neutral current results. The asymmetry parameter A+ is used to demonstrate the parity violation predicted in electroweak interactions. The measurements are well described by the predictions of the Standard Model.

1 data table match query

The polarisation asymmetry measured using the positively and negatively polarised positron beams.


Measurement of K0(S), Lambda, anti-Lambda production at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Eur.Phys.J.C 51 (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.

39 data tables match query

Asymmetry in LAMBDA/LAMBDABAR production in DIS events as a function of transverse momentum (lab). for Q**2 > 25 GeV**2.

Asymmetry in LAMBDA/LAMBDABAR production in DIS events as a function of pseudorapidity (lab). for Q**2 > 25 GeV**2.

Asymmetry in LAMBDA/LAMBDABAR production in DIS events as a function of Bjorken X. for Q**2 > 25 GeV**2.

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Version 2
Search for trilepton resonances from chargino and neutralino pair production in $\sqrt{s}$ = 13 TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Braden Keim ; Abbott, Brad ; et al.
Phys.Rev.D 103 (2021) 112003, 2021.
Inspire Record 1831992 DOI 10.17182/hepdata.99806

A search is performed for the electroweak pair production of charginos and associated production of a chargino and neutralino, each of which decays through an $R$-parity-violating coupling into a lepton and a $W$, $Z$, or Higgs boson. The trilepton invariant-mass spectrum is constructed from events with three or more leptons, targeting chargino decays that include an electron or muon and a leptonically decaying $Z$ boson. The analyzed dataset corresponds to an integrated luminosity of 139 fb$^{-1}$ of proton-proton collision data produced by the Large Hadron Collider at a center-of-mass energy of $\sqrt{s}$ = 13 TeV and collected by the ATLAS experiment between 2015 and 2018. The data are found to be consistent with predictions from the Standard Model. The results are interpreted as limits at 95% confidence level on model-independent cross sections for processes beyond the Standard Model. Limits are also set on the production of charginos and neutralinos for a Minimal Supersymmetric Standard Model with an approximate $B$-$L$ symmetry. Charginos and neutralinos with masses between 100 GeV and 1100 GeV are excluded depending on the assumed decay branching fractions into a lepton (electron, muon, or $\tau$-lepton) plus a boson ($W$, $Z$, or Higgs).

2 data tables match query

$m^{asym}_{Z\ell}$ kinematic distribution in the signal regions showing the data and the post-fit background in sr3$\ell$. The fit uses all CR and SRs, and the distributions are shown inclusively in $m_{Z\ell}$. The full event selection for each of the corresponding regions is applied except for the variable shown, where the selection is indicated by a blue arrow. the first (last) bin includes underflow (overflow) events. The other category mostly consists of $tWZ$, $t\bar{t}W$, and $tZ$ processes. The hatched bands indicate the combined theoretical, experimental, and MC statistical uncertainties. The bottom panel shows the ratio between the data and the post-fit background prediction.

$m^{asym}_{Z\ell}$ kinematic distribution in the signal regions showing the data and the post-fit background in sr3$\ell$. The fit uses all CR and SRs, and the distributions are shown inclusively in $m_{Z\ell}$. The full event selection for each of the corresponding regions is applied except for the variable shown, where the selection is indicated by a blue arrow. the first (last) bin includes underflow (overflow) events. The other category mostly consists of $tWZ$, $t\bar{t}W$, and $tZ$ processes. The hatched bands indicate the combined theoretical, experimental, and MC statistical uncertainties. The bottom panel shows the ratio between the data and the post-fit background prediction.


Deeply Virtual Compton Scattering and its Beam Charge Asymmetry in $e^\pm p$ Collisions at HERA

The H1 collaboration Aaron, F.D. ; Aldaya Martin, M. ; Alexa, C. ; et al.
Phys.Lett.B 681 (2009) 391-399, 2009.
Inspire Record 827347 DOI 10.17182/hepdata.54512

A measurement of elastic deeply virtual Compton scattering gamma* p -> gamma p using e^+ p and e^- p collision data recorded with the H1 detector at HERA is presented. The analysed data sample corresponds to an integrated luminosity of 306 pb^-1, almost equally shared between both beam charges. The cross section is measured as a function of the virtuality Q^2 of the exchanged photon and the centre-of-mass energy W of the gamma* p system in the kinematic domain 6.5 &lt; Q^2 &lt; 80 GeV^2, 30 &lt; W &lt; 140 GeV and |t| &lt; 1 GeV^2, where t denotes the squared momentum transfer at the proton vertex. The cross section is determined differentially in t for different Q^2 and W values and exponential t-slope parameters are derived. Using e^+ p and e^- p data samples, a beam charge asymmetry is extracted for the first time in the low Bjorken x kinematic domain. The observed asymmetry is attributed to the interference between Bethe-Heitler and deeply virtual Compton scattering processes. Experimental results are discussed in the context of two different models, one based on generalised parton distributions and one based on the dipole approach.

1 data table match query

The measured beam charge asymmetry defined as the difference in the DSIG/DPHI distributions between E+ P and E- P collisions.


Tests of the Standard Model in Leptonic Reactions at {PETRA} Energies

The JADE collaboration Bartel, W. ; Becker, L. ; Cords, D. ; et al.
Z.Phys.C 30 (1986) 371, 1986.
Inspire Record 222566 DOI 10.17182/hepdata.48419

An analysis of the three leptonic reactionse+e−→e+e−,μ+μ− andτ+τ− over a wide range of energy,\(12< \sqrt s< 46.78 GeV\) is presented. The data were obtained with the JADE detector at thee+e− storage ring PETRA. They are compared to predictions of electroweak theories, in particular the standard model. For the total cross-sections of all three reactions and for the differential cross-section of Bhabha scattering no deviation from QED is found over the entire energy range. The differential cross-sections of μ and τ pairs at high energies show the angular asymmetry predicted by electroweak interference. The axial-vector and vector weak coupling constant, sin2θW andMZ are determined and compared to other measurements. Finally, limits on deviations from the standard model are given.

6 data tables match query

Forward-Backward Asymmetry measurements.

Forward-Backward Asymmetry measurements.

No description provided.

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Charge Asymmetry and Weak Interaction Effects in $e^+ e^- \to \mu^+ \mu^-$ and $e^+ e^- \to \tau^+ \tau^-$

The TASSO collaboration Brandelik, R. ; Braunschweig, W. ; Gather, K. ; et al.
Phys.Lett.B 110 (1982) 173-180, 1982.
Inspire Record 176719 DOI 10.17182/hepdata.6699

We have measured, at an average centre-of-mass energy of 34.22 GeV a forward-backward charge asymmetry in the reaction e + e − → μ + μ − of value −0.161 ± 0.032. This demonstrates the existence of an axial vector neutral current with coupling strength of g e a g μ a =0.53 ± 0.10. We have also obtained a limit on the vector coupling strength of g e v g μ v <0.12. The Weinberg angle is found to be sin 2 θ W =0.29 +0.09 −0.11 . From the reaction e + e − → τ + τ − we have found g e a g τ a <0.34, g e v g τ v <0.55.

1 data table match query

No description provided.


Deep inelastic scattering with leading protons or large rapidity gaps at HERA

The ZEUS collaboration Chekanov, S. ; Derrick, M. ; Magill, S. ; et al.
Nucl.Phys.B 816 (2009) 1-61, 2009.
Inspire Record 804915 DOI 10.17182/hepdata.52860

The dissociation of virtual photons, $\gamma^{\star} p \to X p$, in events with a large rapidity gap between $X$ and the outgoing proton, as well as in events in which the leading proton was directly measured, has been studied with the ZEUS detector at HERA. The data cover photon virtualities $Q^2>2$ GeV$^2$ and $\gamma^{\star} p$ centre-of-mass energies $40&lt;W&lt;240$ GeV, with $M_X>2$ GeV, where $M_X$ is the mass of the hadronic final state, $X$. Leading protons were detected in the ZEUS leading proton spectrometer. The cross section is presented as a function of $t$, the squared four-momentum transfer at the proton vertex and $\Phi$, the azimuthal angle between the positron scattering plane and the proton scattering plane. It is also shown as a function of $Q^2$ and $\xpom$, the fraction of the proton's momentum carried by the diffractive exchange, as well as $\beta$, the Bjorken variable defined with respect to the diffractive exchange.

4 data tables match query

The azimuthal asymmetries ALT and ATT as a function of X(NAME=POMERON).

The azimuthal asymmetries ALT and ATT as a function of BETA.

The azimuthal asymmetries ALT and ATT as a function of ABS(T).

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New Results on the Reaction $e^+ e^- \to \mu^+ \mu^-$ at $\sqrt{s}=29$-{GeV}

Derrick, M. ; Fernandez, E. ; Fries, R. ; et al.
Phys.Rev.D 31 (1985) 2352, 1985.
Inspire Record 212767 DOI 10.17182/hepdata.3935

We have measured the process e+e−→μ+μ− at √s =29 GeV using the High Resolution Spectrometer at SLAC PEP. The forward-backward charge asymmetry is Aμμ=-(4.9±1.5±0.5)% based on 5057 events. A subsample of 3488 μ+μ− events in the angular range ‖cosθ‖<0.55 gives a cross-section ratio of Rμμ=0.990±0.017±0.030. The resulting couplings of the weak neutral current are gaegaμ=0.208±0.064± 0.021 and gvegvμ=0.027 ±0.051±0.089. The QED cutoff parameters are Λ+>170 GeV and Λ−>146 GeV at 95% C.L.

1 data table match query

Forward-backward asymmetry based on fit to angular distribution. Result is given combined with earlier data from BENDER et al.