Search for lepton flavour violation in the emu continuum 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.
Eur.Phys.J. C72 (2012) 2040, 2012.
Inspire Record 1113445 DOI 10.17182/hepdata.59852

This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark (\={t}) in the emu continuum using 2.1/fb of data collected by the ATLAS detector in sqrt(s) = 7 TeV pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95% C.L. are calculated as a function of the scalar top mass (m_{\={t}}). The upper limits on the production cross section for pp->emuX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for m_{\={t}}=95 GeV to 30 fb for m_{\={t}}=1000 GeV.

3 data tables

The observed E-MU invariant mass distribution plus SM background and signal predicitons for a n stop mass of 95 GeV.

Information about the signal samples used.

The ratios of the observed and expected upper cross section limits to the theoretical cross sections as a function of the scalar top mass.


Search for supersymmetry with jets, missing transverse momentum and at least one hadronically decaying $\tau$ lepton in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett. B714 (2012) 197-214, 2012.
Inspire Record 1111144 DOI 10.17182/hepdata.58918

A search for production of supersymmetric particles in final states containing jets, missing transverse momentum, and at least one hadronically decaying tau lepton is presented. The data were recorded 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 was observed in 2.05 fb-1 of data. The results are interpreted in the context of gauge mediated supersymmetry breaking models with Mmess = 250 TeV, N5 = 3, mu > 0, and Cgrav = 1. The production of supersymmetric particles is excluded at 95% C.L. up to a supersymmetry breaking scale Lambda = 30 Tev, independent of tan(beta), and up to Lambda = 43 TeV for large tan(beta).

11 data tables

Distribution of the missing transverse energy before final selection requirement on the effective mass. Tabulated are the observed Data events, the Standard Model predictions and the expected rates for two signal scenarios with Lambda=30TeV / tan(beta) = 20 and Lambda=40GeV / tan(beta)=30 respectively.

Distribution of the tau pt before final selection requirement on the effective mass. Tabulated are the observed Data events, the Standard Model predictions and the expected rates for two signal scenarios with Lambda=30TeV / tan(beta) = 20 and Lambda=40GeV / tan(beta)=30 respectively.

Distribution of the effective mass before final selection requirement on the effective mass. Tabulated are the observed Data events, the Standard Model predictions and the expected rates for two signal scenarios with Lambda=30TeV / tan(beta) = 20 and Lambda=40GeV / tan(beta)=30 respectively.

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Measurement of the azimuthal anisotropy for charged particle production in $\sqrt{s_{NN}}=2.76$ TeV lead-lead collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. C86 (2012) 014907, 2012.
Inspire Record 1093733 DOI 10.17182/hepdata.59488

Differential measurements of charged particle azimuthal anisotropy are presented for lead-lead collisions at sqrt(s_NN) = 2.76 TeV with the ATLAS detector at the LHC, based on an integrated luminosity of approximately 8 mb^-1. This anisotropy is characterized via a Fourier expansion of the distribution of charged particles in azimuthal angle (phi), with the coefficients v_n denoting the magnitude of the anisotropy. Significant v_2-v_6 values are obtained as a function of transverse momentum (0.5<pT<20 GeV), pseudorapidity (|eta|<2.5) and centrality using an event plane method. The v_n values for n>=3 are found to vary weakly with both eta and centrality, and their pT dependencies are found to follow an approximate scaling relation, v_n^{1/n}(pT) \propto v_2^{1/2}(pT). A Fourier analysis of the charged particle pair distribution in relative azimuthal angle (Dphi=phi_a-phi_b) is performed to extract the coefficients v_{n,n}=<cos (n Dphi)>. For pairs of charged particles with a large pseudorapidity gap (|Deta=eta_a-eta_b|>2) and one particle with pT<3 GeV, the v_{2,2}-v_{6,6} values are found to factorize as v_{n,n}(pT^a,pT^b) ~ v_n(pT^a)v_n(pT^b) in central and mid-central events. Such factorization suggests that these values of v_{2,2}-v_{6,6} are primarily due to the response of the created matter to the fluctuations in the geometry of the initial state. A detailed study shows that the v_{1,1}(pT^a,pT^b) data are consistent with the combined contributions from a rapidity-even v_1 and global momentum conservation. A two-component fit is used to extract the v_1 contribution. The extracted v_1 is observed to cross zero at pT\sim1.0 GeV, reaches a maximum at 4-5 GeV with a value comparable to that for v_3, and decreases at higher pT.

209 data tables

The EP Resolution Factor vs. Centrality for n values from2 to 6.

The Chi Reolution Factor vs. Centrality for n values from 2 to 6.

The one-dimensional Delta(PHI) correlation function vs Delta(PHI) for |DETARAP| in the range 2 to 5 summed over all n values from 1 to 6.

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Jet mass and substructure of inclusive jets in $\sqrt{s}=7$ TeV $pp$ collisions with the ATLAS experiment

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1205 (2012) 128, 2012.
Inspire Record 1094564 DOI 10.17182/hepdata.58739

Recent studies have highlighted the potential of jet substructure techniques to identify the hadronic decays of boosted heavy particles. These studies all rely upon the assumption that the internal substructure of jets generated by QCD radiation is well understood. In this article, this assumption is tested on an inclusive sample of jets recorded with the ATLAS detector in 2010, which corresponds to 35 pb^-1 of pp collisions delivered by the LHC at sqrt(s) = 7 TeV. In a subsample of events with single pp collisions, measurementes corrected for detector efficiency and resolution are presented with full systematic uncertainties. Jet invariant mass, kt splitting scales and n-subjettiness variables are presented for anti-kt R = 1.0 jets and Cambridge-Aachen R = 1.2 jets. Jet invariant-mass spectra for Cambridge-Aachen R = 1.2 jets after a splitting and filtering procedure are also presented. Leading-order parton-shower Monte Carlo predictions for these variables are found to be broadly in agreement with data. The dependence of mean jet mass on additional pp interactions is also explored.

36 data tables

Normalised cross-section as a function of the mass of Cambridge-Aachen jets with R=1.2.

Normalised cross-section as a function of the mass of Cambridge-Aachen jets with R=1.2.

Normalised cross-section as a function of the mass of Cambridge-Aachen jets with R=1.2.

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Search for gluinos in events with two same-sign leptons, jets and missing transverse momentum with the ATLAS detector in $pp$ collisions at $\sqrt{s}=7$ TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 108 (2012) 241802, 2012.
Inspire Record 1094860 DOI 10.17182/hepdata.58682

A search is presented for gluinos decaying via the supersymmetric partner of the top quark using events with two same-sign leptons, jets and missing transverse momentum. The analysis is performed with 2.05 fb^-1 of integrated luminosity from pp collisions at sqrt(s) = 7 TeV collected by the ATLAS detector at the LHC. No excess beyond the Standard Model expectation is observed and exclusion limits are derived for simplified models where the gluino decays via the supersymmetric partner of the top quark and in the MSUGRA/CMSSM framework. In those scenarios, gluino masses below 550 GeV are excluded at 95% CL within the parameter space considered, significantly extending the coverage with respect to existing limits. Depending on the model parameters, gluino masses up to 750 GeV can also be excluded at 95% CL.

9 data tables

Number of jets with pt>50 GeV for events with 2 SS leptons.

Missing transverse momentum distribution for events with 2 SS leptons and at least 4 jets with pt>50 GeV.

Transverse mass distribution for events with 2 SS leptons and at least 4 jets with pt>50 GeV.

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Search for events with large missing transverse momentum, jets, and at least two tau leptons in 7 TeV proton–proton collision data with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett. B714 (2012) 180-196, 2012.
Inspire Record 1095404 DOI 10.17182/hepdata.58711

A search for events with large missing transverse momentum, jets, and at least two tau leptons has been performed using 2 fb^-1 of proton-proton collision data at sqrt(s) = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. No excess above the Standard Model background expectation is observed and a 95% CL visible cross section upper limit for new phenomena is set. A 95% CL lower limit of 32 TeV is set on the GMSB breaking scale Lambda independent of tan(beta). These limits provide the most stringent tests to date in a large part of the considered parameter space.

16 data tables

The observed PT spectrum of the leading TAU candidates and the estimated SM background after pre-selection of candidate events, soft multi-jet rejection and the requirement of two or more TAUS and no light leptons.

The distribution of the effective mass of the two leading TAU candidates in data (with statistical uncertainties only) and the estimated SM background after pre-selection of candidate events, soft multi-jet rejection and the requirement of two or more TAUS and no light leptons.

The distribution of the sum of the transverse masses of the two leading TAU candidates in data (with statistical uncertainties only) and the estimated SM background after pre-selection of candidate events, soft multi-jet rejection and the requirement of two or more TAUS and no light leptons.

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Search for supersymmetry in $pp$ collisions at $\sqrt{s}=7$ TeV in final states with missing transverse momentum and $b^-$ jets with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D85 (2012) 112006, 2012.
Inspire Record 1095236 DOI 10.17182/hepdata.59853

The results of a search for supersymmetry in events with large missing transverse momentum and heavy flavour jets using an integrated luminosity corresponding to 2.05 fb^-1 of pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the Large Hadron Collider are reported. No significant excess is observed with respect to the prediction for Standard Model processes. Results are interpreted in a variety of R-parity conserving models in which scalar bottoms and tops are the only scalar quarks to appear in the gluino decay cascade, and in an SO(10) model framework. Gluino masses up to 600-900 GeV are excluded, depending on the model considered.

41 data tables

Acceptance in the GLUINO-NEUTRALINO plane in the Gbb model for the 1 btag signal region with Meff > 500 GeV.

Acceptance in the GLUINO-NEUTRALINO plane in the Gbb model for the 2 btags signal region with Meff > 500 GeV.

Acceptance in the GLUINO-NEUTRALINO plane in the Gbb model for the 1 btag signal region with Meff > 700 GeV.

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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. D86 (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

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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Measurement of inclusive two-particle angular correlations in pp collisions with the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1205 (2012) 157, 2012.
Inspire Record 1094061 DOI 10.17182/hepdata.59818

We present a measurement of two-particle angular correlations in proton-proton collisions at sqrt(s) = 900 GeV and 7 TeV. The collision events were collected during 2009 and 2010 with the ATLAS detector at the Large Hadron Collider using a single-arm minimum bias trigger. Correlations are measured for charged particles produced in the kinematic range of transverse momentum pT > 100 MeV and pseudorapidity |eta| < 2.5. A complex structure in pseudorapidity and azimuth is observed at both collision energies. Results are compared to Pythia 8 and Herwig++ as well as to the AMBT2B, DW and Perugia 2011 tunes of Pythia 6. The data are not satisfactorily described by any of these models.

5 data tables

Corrected two particle RCORR distribution as a function of Delta(ETARAP) obtained by integrating the foreground and background distributions over Delta(PHI) between 0 and PI.

Corrected two particle RCORR distribution as a function of Delta(ETARAP) obtained by integrating the foreground and background distributions over Delta(PHI) between 0 and PI/2.

Corrected two particle RCORR distribution as a function of Delta(ETARAP) obtained by integrating the foreground and background distributions over Delta(PHI) between PI/2 and PI.

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Measurement of $t \bar{t}$ production with a veto on additional central jet activity in pp collisions at sqrt(s) = 7 TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C72 (2012) 2043, 2012.
Inspire Record 1094568 DOI 10.17182/hepdata.58936
16 data tables

The measured fraction of events, the gap fraction, surviving the veto cut of having no additional jets in the |rapidity| interval < 0.8 having a transverse momentum greater than Q, as a function of Q.

The measured fraction of events, the gap fraction, surviving the veto cut of having no additional jets in the |rapidity| interval 0.8-1.5 having a transverse momentum greater than Q, as a function of Q.

The measured fraction of events, the gap fraction, surviving the veto cut of having no additional jets in the |rapidity| interval 1.5-2.1 having a transverse momentum greater than Q, as a function of Q.

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Measurement of the production cross section of an isolated photon associated with jets in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D85 (2012) 092014, 2012.
Inspire Record 1093738 DOI 10.17182/hepdata.58652

A measurement of the cross section for the production of an isolated photon in association with jets in proton-proton collisions at a center-of-mass energy $\sqrt{s}$ = 7 TeV is presented. Photons are reconstructed in the pseudorapidity range $|\eta^{\gamma}| \lt 1.37$ and with a transverse energy $E_T^\gamma$ > 25 GeV. Jets are reconstructed in the rapidity range $|y^{jet}|$ < 4.4 and with a transverse momentum $p_T^{jet}$ > 20 GeV. The differential cross section $d\sigma/dE_T^\gamma$ is measured, as a function of the photon transverse energy, for three different rapidity ranges of the leading-$p_T$ jet: $|y^{jet}| < 1.2, 1.2 \le |y^{jet}|$ < 2.8 and 2.8 $\le |y^{jet}|$ < 4.4. For each rapidity configuration the same-sign $(\eta^{\gamma}y^{jet}\ge 0)$ and opposite-sign $(\eta^{\gamma}y^{jet}<0)$ cases are studied separately. The results are based on an integrated luminosity of 37 pb$^{-1}$, collected with the ATLAS detector at the LHC. Next-to-leading order perturbative QCD calculations are found to be in fair agreement with the data, except for $E_T^{\gamma} \lt 45$ GeV, where the theoretical predictions overestimate the measured cross sections.

6 data tables

The measured cross section as a function of the photon transverse energy, ET, for pT(jet)>20 GeV, |eta(gamma)|<1.37, |y(jet)|<1.2, eta(gamma)*y(jet)>=0.

The measured cross section as a function of the photon transverse energy, ET, for pT(jet)>20 GeV, |eta(gamma)|<1.37, 1.2<=|y(jet)|<2.8, eta(gamma)*y(jet)>=0.

The measured cross section as a function of the photon transverse energy, ET, for pT(jet)>20 GeV, |eta(gamma)|<1.37, 2.8<=|y(jet)|<4.4, eta(gamma)*y(jet)>=0.

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Forward-backward correlations and charged-particle azimuthal distributions in pp interactions using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1207 (2012) 019, 2012.
Inspire Record 1093734 DOI 10.17182/hepdata.68040

Using inelastic proton-proton interactions at sqrt(s) = 900 GeV and 7 TeV, recorded by the ATLAS detector at the LHC, measurements have been made of the correlations between forward and backward charged-particle multiplicities and, for the first time, between forward and backward charged-particle summed transverse momentum. In addition, jet-like structure in the events is studied by means of azimuthal distributions of charged particles relative to the charged particle with highest transverse momentum in a selected kinematic region of the event. The results are compared with predictions from tunes of the PYTHIA and HERWIG++ Monte Carlo generators, which in most cases are found to provide a reasonable description of the data.

27 data tables

$\sqrt{s} = 900$ GeV, $p_T > 500 $ MeV, $|\eta|<1$.

$\sqrt{s} = 7$ TeV, $p_T > 500 $ MeV, $|\eta|<1$.

$\sqrt{s} = 900$ GeV, $p_T > 500 $ MeV, $|\eta|<2$.

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Search for anomaly-mediated supersymmetry breaking with the ATLAS detector based on a disappearing-track signature in $pp$ collisions at $\sqrt{s}=7$ TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C72 (2012) 1993, 2012.
Inspire Record 1090055 DOI 10.17182/hepdata.58919

In models of anomaly-mediated supersymmetry breaking (AMSB), the lightest chargino is predicted to have a lifetime long enough to be detected in collider experiments. This letter explores AMSB scenarios in pp collisions at sqrt(s) = 7 TeV by attempting to identify decaying charginos which result in tracks that appear to have few associated hits in the outer region of the tracking system. The search was based on data corresponding to an integrated luminosity of 1.02 fb^-1 collected with the ATLAS detector in 2011. The pT spectrum of candidate tracks is found to be consistent with the expectation from Standard Model background processes and constraints on the lifetime and the production cross section were obtained. In the minimal AMSB framework with m_3/2 < 32 TeV, m_0 < 1.5 TeV, tan(beta) = 5 and mu > 0, a chargino having mass below 92 GeV and a lifetime between 0.5 ns and 2 ns is excluded at 95% confidence level.

4 data tables

The pT distribution of candidate tracks with the background prediction.

95% CL upper limits on the production cross section times acceptance as a function of the track pt threshold.

95% CL upper limits on the production cross section as a function of chargino lifetime for the chargino mass of 90.2 GeV.

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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. D85 (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.

100 data tables

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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Rapidity gap cross sections measured with the ATLAS detector in $pp$ collisions at $\sqrt{s}=7$ TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C72 (2012) 1926, 2012.
Inspire Record 1084540 DOI 10.17182/hepdata.58497

Pseudorapidity gap distributions in proton-proton collisions at sqrt(s) = 7 TeV are studied using a minimum bias data sample with an integrated luminosity of 7.1 inverse microbarns. Cross sections are measured differentially in terms of Delta eta F, the larger of the pseudorapidity regions extending to the limits of the ATLAS sensitivity, at eta = +/- 4.9, in which no final state particles are produced above a transverse momentum threshold p_T Cut. The measurements span the region 0 < Delta eta F < 8 for 200 < p_T Cut < 800 MeV. At small Delta eta F, the data test the reliability of hadronisation models in describing rapidity and transverse momentum fluctuations in final state particle production. The measurements at larger gap sizes are dominated by contributions from the single diffractive dissociation process (pp -> Xp), enhanced by double dissociation (pp -> XY) where the invariant mass of the lighter of the two dissociation systems satisfies M_Y <~ 7 GeV. The resulting cross section is d sigma / d Delta eta F ~ 1 mb for Delta eta F >~ 3. The large rapidity gap data are used to constrain the value of the pomeron intercept appropriate to triple Regge models of soft diffraction. The cross section integrated over all gap sizes is compared with other LHC inelastic cross section measurements.

5 data tables

The inelastic cross section differential in the forward rapidity gap size, DELTA(C=RAPGAP) for a maximum observed particle transverse momentum of 200 MeV in the gap.

The inelastic cross section differential in the forward rapidity gap size, DELTA(C=RAPGAP) for a maximum observed particle transverse momentum of 400 MeV in the gap.

The inelastic cross section differential in the forward rapidity gap size, DELTA(C=RAPGAP) for a maximum observed particle transverse momentum of 600 MeV in the gap.

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Measurement of $D^{*+/-}$ meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D85 (2012) 052005, 2012.
Inspire Record 1082009 DOI 10.17182/hepdata.58635

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.

15 data tables

Percentage D*+- production rate R in Z and PT bins.

Percentage D*+- production rate R integrated over jet PT 25-70 GeV as a function of Z.

D*+- production rate R integrated over jet PT=25-70 GeV and Z=0.3-1.0.

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Search for scalar bottom quark pair production with the ATLAS detector in $pp$ Collisions at $\sqrt{s}=7$ TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 108 (2012) 181802, 2012.
Inspire Record 1081778 DOI 10.17182/hepdata.58516

The results of a search for pair production of the scalar partners of bottom quarks in 2.05 fb^-1 of pp collisions at sqrt{s} = 7 TeV using the ATLAS experiment are reported. Scalar bottoms are searched for in events with large missing transverse momentum and two jets in the final state, where both jets are identified as originating from a b-quark. In an R-parity conserving minimal supersymmetric scenario, assuming that the scalar bottom decays exclusively into a bottom quark and a neutralino, 95% confidence-level upper limits are obtained in the tilde{b}_1 - tilde{chi}^0_1 mass plane such that for neutralino masses below 60 GeV scalar bottom masses up to 390 GeV are excluded.

6 data tables

Observed 95% CL exclusion limit in the sbottom-neutralino mass plane.

Observed 95% CL exclusion limit in the sbottom-neutralino mass plane with the renormalization and factorization scales set to mu/2.

Observed 95% CL exclusion limit in the sbottom-neutralino mass plane with the renormalization and factorization scales set to 2*mu.

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Measurement of inclusive jet and dijet production in $pp$ collisions at $\sqrt{s}=7$ TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D86 (2012) 014022, 2012.
Inspire Record 1082936 DOI 10.17182/hepdata.58163

Inclusive jet and dijet cross sections have been measured in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector at the Large Hadron Collider. The cross sections were measured using jets clustered with the anti-kT algorithm with parameters R=0.4 and R=0.6. These measurements are based on the 2010 data sample, consisting of a total integrated luminosity of 37 inverse picobarns. Inclusive jet double-differential cross sections are presented as a function of jet transverse momentum, in bins of jet rapidity. Dijet double-differential cross sections are studied as a function of the dijet invariant mass, in bins of half the rapidity separation of the two leading jets. The measurements are performed in the jet rapidity range |y|<4.4, covering jet transverse momenta from 20 GeV to 1.5 TeV and dijet invariant masses from 70 GeV to 5 TeV. The data are compared to expectations based on next-to-leading order QCD calculations corrected for non-perturbative effects, as well as to next-to-leading order Monte Carlo predictions. In addition to a test of the theory in a new kinematic regime, the data also provide sensitivity to parton distribution functions in a region where they are currently not well-constrained.

32 data tables

Inclusive jet PT distribution for the |y| range 0.0-0.3 and R=0.4.

Inclusive jet PT distribution for the |y| range 0.3-0.8 and R=0.4.

Inclusive jet PT distribution for the |y| range 0.8-1.2 and R=0.4.

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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. D85 (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

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.

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Kshort and $\Lambda$ production in $pp$ interactions at $\sqrt{s}=0.9$ and 7 TeV measured with the ATLAS detector at the LHC

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D85 (2012) 012001, 2012.
Inspire Record 944826 DOI 10.17182/hepdata.58341

The production of Kshort and Lambda hadrons is studied in inelastic pp collisions at sqrt(s) = 0.9 and 7 TeV collected with the ATLAS detector at the LHC using a minimum-bias trigger. The observed distributions of transverse momentum, rapidity, and multiplicity are corrected to hadron level in a model-independent way within well defined phase-space regions. The distribution of the production ratio of Lambdabar to Lambda baryons is also measured. The results are compared with various Monte Carlo simulation models. Although most of these models agree with data to within 15% in the Kshort distributions, substantial disagreements with data are found in the Lambda distributions of transverse momentum.

16 data tables

The corrected transverse momentum distribution of KS mesons at 7000 GeV.

The corrected rapidity distribution of KS mesons at 7000 GeV.

The corrected multiplicity distribution of KS mesons at 7000 GeV.

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Measurement of the $W^\pm Z$ production cross section and limits on anomalous triple gauge couplings in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett. B709 (2012) 341-357, 2012.
Inspire Record 954993 DOI 10.17182/hepdata.68039

This Letter presents a measurement of WZ production in 1.02 fb^-1 of pp collision data at sqrt(s) = 7 TeV collected by the ATLAS experiment in 2011. Doubly leptonic decay events are selected with electrons, muons and missing transverse momentum in the final state. In total 71 candidates are observed, with a background expectation of 12.1 +/- 1.4(stat.) +4.1/-2.0(syst) events. The total cross section for WZ production for Z gamma^* masses within the range 66 GeV to 116 GeV is determined to be sigma_WZ^tot = 20.5 +3.1/-2.8(stat.) +1.4/-1.3(syst.) +0.9/-0.8(lumi.)pb, which is consistent with the Standard Model expectation of 17.3 +1.3/-0.8 pb. Limits on anomalous triple gauge boson couplings are extracted.

1 data table

Total fiducial cross-section $WZ\to\ell\nu\ell\ell$.


Search for Massive Colored Scalars in Four-Jet Final States in $\sqrt{s}=7$ TeV proton-proton collisions with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C71 (2011) 1828, 2011.
Inspire Record 939560 DOI 10.17182/hepdata.58020

A search for pair-produced scalar particles decaying to a four-jet final state is presented. The analysis is performed using an integrated luminosity of 34 pb^-1 recorded by the ATLAS detector in 2010. No deviation from the Standard Model is observed. For a scalar mass of 100 GeV (190 GeV) the limit on the scalar gluon pair production cross section at 95% confidence level is 1 nb (0.28 nb). When these results are interpreted as mass limits, scalar-gluons (hyperpions) with masses of 100 to 185 GeV (100 to 155 GeV) are excluded at 95% confidence level with the exception of a mass window of width about 5 GeV (15 GeV) around 140 GeV.

9 data tables

The distributions of the momentum of the 4th jet.

The di-jet delta(R) distribution for the sgluon candidate with the highest PT jet after applying the PT cut of 55 GeV and pairing the four leading jets into 2 sgluon candidates.

The distribution in relative mass difference of the two sgluon candidates after application of the PT and di-jet delta(R) cuts.

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Search for new phenomena in final states with large jet multiplicities and missing transverse momentum using $\sqrt{s}=7$ TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1111 (2011) 099, 2011.
Inspire Record 939504 DOI 10.17182/hepdata.58120

Results are presented of a search for any particle(s) decaying to six or more jets in association with missing transverse momentum. The search is performed using 1.34 fb^-1 of sqrt(s)=7 TeV proton-proton collisions recorded by the ATLAS detector during 2011. Data-driven techniques are used to determine the backgrounds in kinematic regions that require at least six, seven or eight jets, well beyond the multiplicities required in previous analyses. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a supersymmetry model (MSUGRA/CMSSM) where they extend previous constraints.

18 data tables

Observed and predicted distributions of the variable ET(C=MISSING)/SQRT(HT) for events with exactly 6 jets each having PT > 55 GeV.

Observed and predicted distributions of the variable ET(C=MISSING)/SQRT(HT) for events with exactly 5 jets each having PT > 80 GeV.

Observed and predicted jet multiplicity distribution for jets with PT > 55 Gev in the ET(C=MISSING)/SQRT(HT) region 1.5-2 GeV.

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Searches for supersymmetry with the ATLAS detector using final states with two leptons and missing transverse momentum in $\sqrt{s}=7$ TeV proton-proton collisions

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett. B709 (2012) 137-157, 2012.
Inspire Record 943401 DOI 10.17182/hepdata.58447

Results of three searches are presented for the production of supersymmetric particles decaying into final states with missing transverse momentum and exactly two isolated leptons, e or mu. The analysis uses a data sample collected during the first half of 2011 that corresponds to a total integrated luminosity of 1 fb^-1 of sqrt{s} = 7 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider. Opposite-sign and same-sign dilepton events are separately studied, with no deviations from the Standard Model expectation observed. Additionally, in opposite- sign events, a search is made for an excess of same-flavour over different-flavour lepton pairs. Effective production cross sections in excess of 9.9 fb for opposite-sign events containing supersymmetric particles with missing transverse momentum greater than 250 GeV are excluded at 95% CL. For same-sign events containing supersymmetric particles with missing transverse momentum greater than 100 GeV, effective production cross sections in excess of 14.8 fb are excluded at 95% CL. The latter limit is interpreted in a simplified weak gaugino production model excluding chargino masses up to 200 GeV.

18 data tables

The dilepton invariant mass distribution for same-sign dileptons.

The missing-mass ET distribution for same-sign dilepton events before any jet requirement.

The missing-mass ET distribution for same-sign dilepton events after requiring two high-pt jets.

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Search for a heavy neutral particle decaying into an electron and a muon using 1 fb$^{-1}$ of ATLAS data

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C71 (2011) 1809, 2011.
Inspire Record 927405 DOI 10.17182/hepdata.58152

A search is presented for a high mass neutral particle that decays directly to the emu final state. The data sample was recorded by the ATLAS detector in sqrt(s) = 7 TeV pp collisions at the LHC from March to June 2011 and corresponds to an integrated luminosity of 1.07 fb^-1. The data are found to be consistent with the Standard Model background. The high emu mass region is used to set 95% confidence level upper limits on the production of two possible new physics processes: tau sneutrinos in an R-parity violating supersymmetric model and Z'-like vector bosons in a lepton flavor violating model.

9 data tables

Observed and predicted E-MU invariant mass distributions.

Observed and predicted electron PT distributions.

Observed and predicted muon PT distributions.

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