Study of jets produced in association with a $W$ boson in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 85 (2012) 092002, 2012.
Inspire Record 1083318 DOI 10.17182/hepdata.39682

We report a study of final states containing a W boson and hadronic jets, produced in proton-proton collisions at a center-of-mass energy of 7 TeV. The data were collected with the ATLAS detector at the CERN LHC and comprise the full 2010 data sample of 36 pb^-1. Cross sections are determined using both the electron and muon decay modes of the W boson and are presented as a function of inclusive jet multiplicity, N_jet, for up to five jets. At each multiplicity, cross sections are presented as a function of jet transverse momentum, the scalar sum of the transverse momenta of the charged lepton, missing transverse momentum, and all jets, the invariant mass spectra of jets, and the rapidity distributions of various combinations of leptons and final-state jets. The results, corrected for all detector effects and for all backgrounds such as diboson and top quark pair production, are compared with particle-level predictions from perturbative QCD. Leading-order multiparton event generators, normalized to the NNLO total cross section for inclusive W-boson production, describe the data reasonably well for all measured inclusive jet multiplicities. Next-to-leading-order calculations from MCFM, studied here for N_jet >= 2, and BlackHat-Sherpa, studied here for N_jet >= 4, are found to be mostly in good agreement with the data.

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The measured W+jets cross section as a function of the jet multiplicity for jet PT > 30 GeV shown for "Born" leptons and for QED corrected "dressed" leptons.

The measured W+jets cross section ratio as a function of jet multiplicity for jet PT > 30 GeV.

The measured W+jets cross section as a function of the pT of the first jet in the event for jet multiplicities >= 1 and jet PT > 30 GeV shown for "Born" leptons and for QED corrected "dressed" leptons.

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Search for doubly-charged Higgs bosons in like-sign dilepton final states at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J.C 72 (2012) 2244, 2012.
Inspire Record 1191430 DOI 10.17182/hepdata.40316

A search for doubly-charged Higgs bosons decaying to pairs of electrons and/or muons is presented. The search is performed using a data sample corresponding to an integrated luminosity of 4.7 fb-1 of pp collisions at sqrt(s) = 7 TeV collected by the ATLAS detector at the LHC. Pairs of prompt, isolated, high-pT leptons with the same electric charge (ee, emu, mumu) are selected, and their invariant mass distribution is searched for a narrow resonance. No significant excess over Standard Model background expectations is observed, and limits are placed on the cross section times branching ratio for pair production of doubly-charged Higgs bosons. The masses of doubly-charged Higgs bosons are constrained depending on the branching ratio into these leptonic final states. Assuming pair production, coupling to left-handed fermions, and a branching ratio of 100% for each final state, masses below 409 GeV, 375 GeV, and 398 GeV are excluded for ee, emu, mumu, respectively.

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The upper mass limit of the doubly charged Higgs boson as a function of its branching ratio to like sign lepton pairs assuming coupling to left-handed fermions. The results are given separately for each of the lepton pair combinations, electron-electron, electon-muon and muon-muon.

The upper mass limit of the doubly charged Higgs boson as a function of its branching ratio to like sign lepton pairs assuming coupling to right-handed fermions. The results are given separately for each of the lepton pair combinations, electron-electron, electon-muon and muon-muon.


Search for dark matter candidates and large extra dimensions in events with a photon and missing transverse momentum in $pp$ collision data at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.Lett. 110 (2013) 011802, 2013.
Inspire Record 1186740 DOI 10.17182/hepdata.47282

Results of a search for new phenomena in events with an energetic photon and large missing transverse momentum in proton-proton collisions at sqrt(s)=7 TeV are reported. Data collected by the ATLAS experiment at the LHC corresponding to an integrated luminosity of 4.6 fb-1 are used. Good agreement is observed between the data and the Standard Model predictions. The results are translated into exclusion limits on models with large extra spatial dimensions and on pair production of weakly interacting dark matter candidates.

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95% CL observed and expected upper limits on M_D as a function of the number of extra-dimensions considering LO signal cross sections. The impact of the +-1sigma theoretical uncertainty on the observed limits and the expected +-1sigma range of limits in the absence of a signal are also given.

95% CL observed and expected upper limits on M_D as a function of the number of extra-dimensions considering NLO signal cross sections. The impact of the +-1sigma theoretical uncertainty on the observed limits and the expected +-1sigma range of limits in the absence of a signal are also given.

95% CL observed and expected upper limits on M_* for spin-independent (D1) WIMP models. The impact of the +-1sigma theoretical uncertainty on the observed limits and the expected +-1sigma range of limits in the absence of a signal are also given.

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Measurement of jet shapes in top-quark pair events at $\sqrt{s}$ = 7 TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J.C 73 (2013) 2676, 2013.
Inspire Record 1243871 DOI 10.17182/hepdata.62685

A measurement of jet shapes in top-quark pair events using 1.8 fb$^{-1}$ of $\sqrt{s}$ = 7 TeV pp collision data recorded by the ATLAS detector is presented. Samples of top-quark pair events are selected in both the single-lepton and dilepton final states. The differential and integrated shapes of the jets initiated by bottom-quarks from the top-quark decays are compared with those of the jets originated by light-quarks from the hadronic W-boson decays $W \to q\bar{q}'$ in the single-lepton channel. The light-quark jets are found to have a narrower distribution of the momentum flow inside the jet area than b-quark jets.

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Differential jet shape as a function of the radius r for the PT range 30-40 GeV.

Integrated jet shape as a function of the radius r for the PT range 30-40 GeV.

Differential jet shape as a function of the radius r for the PT range 40-50 GeV.

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Measurement of the distributions of event-by-event flow harmonics in lead-lead collisions at = 2.76 TeV with the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 11 (2013) 183, 2013.
Inspire Record 1233359 DOI 10.17182/hepdata.62783

The distributions of event-by-event harmonic flow coefficients v_n for n=2-4 are measured in sqrt(s_NN)=2.76 TeV Pb+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using charged particles with transverse momentum pT> 0.5 GeV and in the pseudorapidity range |eta|<2.5 in a dataset of approximately 7 ub^-1 recorded in 2010. The shapes of the v_n distributions are described by a two-dimensional Gaussian function for the underlying flow vector in central collisions for v_2 and over most of the measured centrality range for v_3 and v_4. Significant deviations from this function are observed for v_2 in mid-central and peripheral collisions, and a small deviation is observed for v_3 in mid-central collisions. It is shown that the commonly used multi-particle cumulants are insensitive to the deviations for v_2. The v_n distributions are also measured independently for charged particles with 0.5<pT<1 GeV and pT>1 GeV. When these distributions are rescaled to the same mean values, the adjusted shapes are found to be nearly the same for these two pT ranges. The v_n distributions are compared with the eccentricity distributions from two models for the initial collision geometry: a Glauber model and a model that includes corrections to the initial geometry due to gluon saturation effects. Both models fail to describe the experimental data consistently over most of the measured centrality range.

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The relationship between centrality intervals and MEAN(Npart) estimated from the Glauber model.

The MEAN(Npart) dependence of MEAN(V2) for three pT ranges together with the total systematic uncertainties.

The MEAN(Npart) dependence of SIGMA(V2) for three pT ranges together with the total systematic uncertainties.

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Observation of Associated Near-Side and Away-Side Long-Range Correlations in $\sqrt{s_{NN}}$=5.02 TeV Proton-Lead Collisions with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.Lett. 110 (2013) 182302, 2013.
Inspire Record 1208304 DOI 10.17182/hepdata.62784

Two-particle correlations in relative azimuthal angle ($\Delta-\phi$) and pseudorapidity ($\Delta-\eta$) are measured in $\sqrt{s_{NN}}$ = 5.02 TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1 $\mu b^{-1}$ of data as a function of $p_T$ and the transverse energy ($\sum E_T^{Pb}$) summed over 3.1 < $\eta$ < 4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|$\Delta-\eta$|<5) near-side ($\Delta-\phi$ ~ 0) correlation that grows rapidly with increasing $\sum E_T^{Pb}$. A long-range away-side ($\Delta-\phi$ ~ pi) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small $\sum E_T^{Pb}$, is found to match the near-side correlation in magnitude, shape (in $\Delta-\eta$ and $\Delta-\phi$) and $\sum E_T^{Pb}$ dependence. The resultant $\Delta-\phi$ correlation is approximately symmetric about $\pi$/2, and is consistent with a cos(2$\Delta-\phi$) modulation for all $\sum E_T^{Pb}$ ranges and particle $p_T$. The amplitude of this modulation is comparable in magnitude and $p_T$ dependence to similar modulations observed in heavy-ion collisions, suggestive of final-state collective effects in high multiplicity events.

127 data tables match query

Distribution of per-trigger yield, Y(DELTA(PHI)), in the peripheral and the central event activity classes and their differences, for 0.3 < pT(a) < 0.5 GeV and 0.5 < pT(b) < 4 GeV.

Distribution of per-trigger yield, Y(DELTA(PHI)), in the peripheral and the central event activity classes and their differences, for 0.5 < pT(a) < 1 GeV and 0.5 < pT(b) < 4 GeV.

Distribution of per-trigger yield, Y(DELTA(PHI)), in the peripheral and the central event activity classes and their differences, for 1 < pT(a) < 2 GeV and 0.5 < pT(b) < 4 GeV.

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Search for charginos nearly mass degenerate with the lightest neutralino based on a disappearing-track signature in pp collisions at $\sqrt(s)$=8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.D 88 (2013) 112006, 2013.
Inspire Record 1258398 DOI 10.17182/hepdata.62699

A search is presented for direct chargino production based on a disappearing-track signature using 20.3 fb-1 of proton-proton collisions at sqrt(s) = 8 TeV collected with the ATLAS experiment at the LHC. In anomaly-mediated supersymmetry breaking (AMSB) models, the lightest chargino is nearly mass-degenerate with the lightest neutralino and its lifetime is long enough to be detected in the tracking detectors by identifying decays that result in tracks with no associated hits in the outer region of the tracking system. Some models with supersymmetry also predict charginos with a significant lifetime. This analysis attains sensitivity for charginos with a lifetime between 0.1 ns and 10 ns, and significantly surpasses the reach of the LEP experiments. No significant excess above the background expectation is observed for candidate tracks with large transverse momentum, and constraints on chargino properties are obtained. In the AMSB scenarios, a chargino mass below 270 GeV is excluded at 95% confidence level.

13 data tables match query

The pT distribution of disappearing-track candidates.

Observed CLs contour in the ( M(CHARGINO), TAU(CHARGINO) ) space for tan(beta) = 5 and mu > 0.

Observed CLs contour with minus 1-sigma signal cross-section uncertainty in the ( M(CHARGINO), TAU(CHARGINO) ) space for tan(beta) = 5 and mu > 0.

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Measurement of $ZZ$ production in $pp$ collisions at $\sqrt{s}=7$ TeV and limits on anomalous $ZZZ$ and $ZZ\gamma$ couplings with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 03 (2013) 128, 2013.
Inspire Record 1203852 DOI 10.17182/hepdata.62535

A measurement of the ZZ production cross section in proton-proton collisions at sqrt(s) = 7 TeV using data recorded by the ATLAS experiment at the Large Hadron Collider is presented. In a data sample corresponding to an integrated luminosity of 4.6 fb-1 collected in 2011, events are selected that are consistent either with two Z bosons decaying to electrons or muons or with one Z boson decaying to electrons or muons and a second Z boson decaying to neutrinos. The ZZ*->llll and ZZ->llnunu cross sections are measured in restricted phase-space regions. These results are then used to derive the total cross section for ZZ events produced with both Z bosons in the mass range 66 to 116 GeV, sigmaZZtot = 6.7 +-0.7 +0.4-0.3 +-0.3 pb, which is consistent with the Standard Model prediction of 5.89+0.22-0.18 pb calculated at next-to-leading order in QCD. The normalized differential cross sections in bins of various kinematic variables are presented. Finally, the differential event yield as a function of the transverse momentum of the leading Z boson is used to set limits on anomalous neutral triple gauge boson couplings in ZZ production.

8 data tables match query

The measured fiducial cross sections. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity.

The measured total cross sections. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity.

Normalized ZZ fiducial cross section (multiplied by 10^6 for readability) in bins of the leading reconstructed dilepton pT for the 4 lepton channel. The first systematic uncertainty is detector systematics, the second is background systematic uncertainties.

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Measurement of the electroweak production of dijets in association with a Z-boson and distributions sensitive to vector boson fusion in proton-proton collisions at $\sqrt{s} =$ 8 TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 04 (2014) 031, 2014.
Inspire Record 1279489 DOI 10.17182/hepdata.62729

Measurements of fiducial cross sections for the electroweak production of two jets in association with a Z-boson are presented. The measurements are performed using 20.3 inverse femtobarns of proton-proton collision data collected at a centre-of-mass energy of sqrt(s)=8 TeV by the ATLAS experiment at the Large Hadron Collider. The electroweak component is extracted by a fit to the dijet invariant mass distribution in a fiducial region chosen to enhance the electroweak contribution over the dominant background in which the jets are produced via the strong interaction. The electroweak cross sections measured in two fiducial regions are in good agreement with the Standard Model expectations and the background-only hypothesis is rejected with significance above the 5 sigma level. The electroweak process includes the vector boson fusion production of a Z-boson and the data are used to place limits on anomalous triple gauge boson couplings. In addition, measurements of cross sections and differential distributions for inclusive Z-boson-plus-dijet production are performed in five fiducial regions, each with different sensitivity to the electroweak contribution. The results are corrected for detector effects and compared to predictions from the SHERPA and POWHEG event generators.

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Unfolded normalised differential Z+2j cross section as a function of dijet invariant mass in the baseline region.

Unfolded normalised differential Z+2j cross section as a function of dijet invariant mass in the search region.

Unfolded normalised differential Z+2j cross section as a function of the rapidity separation between the leading jets in the baseline region.

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Search for stable hadronising squarks and gluinos with the ATLAS experiment at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett.B 701 (2011) 1-19, 2011.
Inspire Record 892044 DOI 10.17182/hepdata.58184

Hitherto unobserved long-lived massive particles with electric and/or colour charge are predicted by a range of theories which extend the Standard Model. In this paper a search is performed at the ATLAS experiment for slow-moving charged particles produced in proton-proton collisions at 7 TeV centre-of-mass energy at the LHC, using a data-set corresponding to an integrated luminosity of 34 pb-1. No deviations from Standard Model expectations are found. This result is interpreted in a framework of supersymmetry models in which coloured sparticles can hadronise into long-lived bound hadronic states, termed R-hadrons, and 95% CL limits are set on the production cross-sections of squarks and gluinos. The influence of R-hadron interactions in matter was studied using a number of different models, and lower mass limits for stable sbottoms and stops are found to be 294 and 309 GeV respectively. The lower mass limit for a stable gluino lies in the range from 562 to 586 GeV depending on the model assumed. Each of these constraints is the most stringent to date.

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Distribution of the observed rate of energy loss in the Pixel detector plus the simulated background and model estimates for three gluino masses.

Distribution of the observed BETA values in the Tile Calorimeter plus the simulated background and model estimates for three gluino masses.

Distribution of the heavy particle Mass estimated from the Pixel detector data plus the simulated background and model estimates for three gluino masses. A cut of dE/dx > 1.1 MeV/(gm*cm**2) is imposed.;.

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Properties of jets measured from tracks in proton-proton collisions at center-of-mass energy $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 84 (2011) 054001, 2011.
Inspire Record 919017 DOI 10.17182/hepdata.57743

Jets are identified and their properties studied in center-of-mass energy sqrt(s) = 7 TeV proton-proton collisions at the Large Hadron Collider using charged particles measured by the ATLAS inner detector. Events are selected using a minimum bias trigger, allowing jets at very low transverse momentum to be observed and their characteristics in the transition to high-momentum fully perturbative jets to be studied. Jets are reconstructed using the anti-kt algorithm applied to charged particles with two radius parameter choices, 0.4 and 0.6. An inclusive charged jet transverse momentum cross section measurement from 4 GeV to 100 GeV is shown for four ranges in rapidity extending to 1.9 and corrected to charged particle-level truth jets. The transverse momenta and longitudinal momentum fractions of charged particles within jets are measured, along with the charged particle multiplicity and the particle density as a function of radial distance from the jet axis. Comparison of the data with the theoretical models implemented in existing tunings of Monte Carlo event generators indicates reasonable overall agreement between data and Monte Carlo. These comparisons are sensitive to Monte Carlo parton showering, hadronization, and soft physics models.

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Double differential cross sections for charged particle jets as a function of the jet PT in the |rapidity| range 0.0-0.5, shown separately for the two R values. The first (sys) errors is the correlated efficiency uncertainty and the second (sys) error is the correlated vetex splitting uncertainty. The third (sys) error is the quadratic sum of all the uncorrelated systematic uncertainties.

Double differential cross sections for charged particle jets as a function of the jet PT in the |rapidity| range 0.5-1.0, shown separately for the two R values. The first (sys) errors is the correlated efficiency uncertainty and the second (sys) error is the correlated vetex splitting uncertainty. The third (sys) error is the quadratic sum of all the uncorrelated systematic uncertainties.

Double differential cross sections for charged particle jets as a function of the jet PT in the |rapidity| range 1.0-1.5, shown separately for the two R values. The first (sys) errors is the correlated efficiency uncertainty and the second (sys) error is the correlated vetex splitting uncertainty. The third (sys) error is the quadratic sum of all the uncorrelated systematic uncertainties.

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Search for squarks and gluinos using final states with jets and missing transverse momentum with the ATLAS detector in $\sqrt{s}=7$ TeV proton-proton collisions

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett.B 710 (2012) 67-85, 2012.
Inspire Record 930002 DOI 10.17182/hepdata.57987

A search for squarks and gluinos in events containing jets, missing transverse momentum and no electrons or muons is presented. The data were recorded in 2011 by the ATLAS experiment in sqrt(s) = 7 TeV proton-proton collisions at the Large Hadron Collider. No excess above the Standard Model background expectation is observed in 1.04 fb^-1 of data. Gluino and squark masses below 700 GeV and 875 GeV respectively are excluded at the 95% confidence level in simplified models containing only squarks of the first two generations, a gluino octet and a massless neutralino. The exclusion limit increases to 1075 GeV for squarks and gluinos of equal mass. In MSUGRA/CMSSM models with tan(beta)=10, A_0=0 and mu> 0, squarks and gluinos of equal mass are excluded for masses below 950 GeV. These limits extend the region of supersymmetric parameter space excluded by previous measurements.

10 data tables match query

The distribution in Meff (scalar sum of the missing transverse momentum and the transverse momenta of the two highest pT jets) for events with at least 2 jets after the application of all selection criteria (other than the Meff cut itself). The table shows the number of observed data points per 100 GeV bin plus the background prediction of the Standard-Model Monte-Carlo and its upper and lower 1-sigma error limits uncertainty band.

The distribution in Meff (scalar sum of the missing transverse momentum and the transverse momenta of the three highest pT jets) for events with at least 3 jets after the application of all selection criteria (other than the Meff cut itself). The table shows the number of observed data points per 100 GeV bin plus the background prediction of the Standard-Model Monte-Carlo and its upper and lower 1-sigma error limits uncertainty band.

The distribution in Meff (scalar sum of the missing transverse momentum and the transverse momenta of the four highest pT jets) for events with at least 4 jets after the application of all selection criteria (other than the Meff cut itself). The table shows the number of observed data points per 100 GeV bin plus the background prediction of the Standard-Model Monte-Carlo and its upper and lower 1-sigma error limits uncertainty band.

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Measurement of the Inelastic Proton-Proton Cross-Section at $\sqrt{s}=7$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Nature Commun. 2 (2011) 463, 2011.
Inspire Record 894867 DOI 10.17182/hepdata.58283

A first measurement of the inelastic cross-section is presented for proton-proton collisions at a center of mass energy sqrt{s}=7 TeV using the ATLAS detector at the Large Hadron Collider. In a dataset corresponding to an integrated luminosity of 20 mub-1, events are selected by requiring hits on scintillation counters mounted in the forward region of the detector. An inelastic cross-section of $60.3 +/- 2.1 mb is measured for xi > 5x10^-6, where xi=M_X^2/s is calculated from the invariant mass, M_X, of hadrons selected using the largest rapidity gap in the event. For diffractive events this corresponds to requiring at least one of the dissociation masses to be larger than 15.7 GeV.

1 data table match query

The measured and extrapolated inelastic cross section. The first error is the experimental error and the second (sys) error is the error in the extrapolation.


Measurement of the azimuthal ordering of charged hadrons with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 86 (2012) 052005, 2012.
Inspire Record 1091481 DOI 10.17182/hepdata.58477

This paper presents a measurement of the ordering of charged hadrons in the azimuthal angle relative to the beam axis in high-energy proton-proton collisions at the Large Hadron Collider (LHC). A spectral analysis of correlations between longitudinal and transverse components of the momentum of the charged hadrons, driven by the search for phenomena related to the structure of the QCD field, is performed. Data were recorded with the ATLAS detector at centre-of-mass energies of sqrt(s) = 900 GeV and sqrt(s) = 7 TeV. The correlations measured in a phase space region dominated by low-pT particles are not well described by conventional models of hadron production. The measured spectra show features consistent with the fragmentation of a QCD string represented by a helix-like ordered gluon chain.

4 data tables match query

The corrected data for the power spectra S_E for the three different data samples at a centre-of-mass energy of 7 TeV.

The corrected data for the power spectra S_ETA for the three different data samples at a centre-of-mass energy of 7 TeV.

The corrected data for the power spectra S_E for the three different data samples at a centre-of-mass energy of 900 GeV.

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Search for a heavy particle decaying into an electron and a muon with the ATLAS detector in $\sqrt{s}=7$ TeV $pp$ collisions at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 106 (2011) 251801, 2011.
Inspire Record 894358 DOI 10.17182/hepdata.57150

This Letter presents the first search for a heavy particle decaying into an e\mu final state in sqrt(s)=7 TeV pp collisions at the LHC. The data were recorded by the ATLAS detector during 2010 and correspond to a total integrated luminosity of 35/pb. No excess above the Standard Model background expectation is observed. Exclusions at 95% confidence level are placed on two representative models. In an R-parity violating supersymmetric model, tau sneutrinos with a mass below 0.75 TeV are excluded, assuming single coupling dominance and the couplings lambda'_{311}=0.11, lambda_{312}=0.07. In a lepton flavor violating model, a Z'-like vector boson with masses of 0.70 to 1.00 TeV and corresponding cross sections times branching ratios of 0.175 to 0.183 pb is excluded. These results extend to higher mass RPV sneutrinos and LFV Z's than previous constraints from the Tevatron.

4 data tables match query

Observed e-mu invariant mass distribution.

The observed 95% CL upper limits on the cross section for p p --> sneutrino x BR(sneutrino -> e-mu) as a function of the sneutrino mass.

The 95% CL upper limits on the Lambda311 coupling as a function of the sneutrino mass, for threee values of Lambda312.

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Measurement of the production cross section for Z/gamma* in association with jets in $pp$ collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.D 85 (2012) 032009, 2012.
Inspire Record 945498 DOI 10.17182/hepdata.58228

Results are presented on the production of jets of particles in association with a Z/gamma* boson, in proton-proton collisions at sqrt(s) = 7 TeV with the ATLAS detector. The analysis includes the full 2010 data set, collected with a low rate of multiple proton-proton collisions in the accelerator, corresponding to an integrated luminosity of 36 pb^-1. Inclusive jet cross sections in Z/gamma* events, with Z/gamma* decaying into electron or muon pairs, are measured for jets with transverse momentum pT > 30 GeV and jet rapidity |y| < 4.4. The measurements are compared to next-to-leading-order perturbative QCD calculations, and to predictions from different Monte Carlo generators implementing leading-order matrix elements supplemented by parton showers.

24 data tables match query

Cross section for Inclusive Jet Multiplicity corrected to the lepton common fiducial region and for QED radiation effects.

Ratio of cross sections for N/N-1 inclusive jet multiplicities corrected to the lepton common fiducial region and for QED radiation effects.

Inclusive jet differential cross section dsigma/dpt corrected to the lepton common fiducial region and for QED radiation effects.