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CERN-LHC. Measurements of cross sections for final states containing a W boson and hadronic jets in proton-proton collisions at a centre-of-mass energy of 7 TeV. The data is from the full 2010 sample with a total integrated luminosity of 36 pb^{-1}. Cross sections are measured in both the electron and muon decay modes of the W and are presented as a function of inclusive jet multiplicity up to five jets. For each multiplicity, cross sections are determined as a function of (1) each jet PT, (2) the scalar sum (HT) of the PT of the charged lepton, missing PT and all jets, (3) the invariant mass of the jets and (4) rapidity distributions of various combinations of leptons and jets. The results are corrected for all detector effects and all known backgrounds. Comparative results are also shown for particle-level predicitions from ALPGEN, SHERPA and BLACKHAT-SHERPA. A separate link gives the Non-Perturbative and QED correction for each table. Note added (26 JUN 2014): The cross section values reported in Tables 1, 3-25, 51, 53-75 below should be multiplied by a factor of 1.0187 to take into account the updated value of the integrated luminosity for the ATLAS 2010 data taking period. The uncertainty on the global normalisation ("Lumi") increases slightly from 3.4% to 3.5%. See Eur.Phys.J. C73 (2013) 2518 for more details. The predicted W+jets cross section as a function of the invariant mass of the first+second jets for jet multiplicites >= 2 and jet PT > 30 GeV.

CERN-LHC. Measurements of cross sections for final states containing a W boson and hadronic jets in proton-proton collisions at a centre-of-mass energy of 7 TeV. The data is from the full 2010 sample with a total integrated luminosity of 36 pb^{-1}. Cross sections are measured in both the electron and muon decay modes of the W and are presented as a function of inclusive jet multiplicity up to five jets. For each multiplicity, cross sections are determined as a function of (1) each jet PT, (2) the scalar sum (HT) of the PT of the charged lepton, missing PT and all jets, (3) the invariant mass of the jets and (4) rapidity distributions of various combinations of leptons and jets. The results are corrected for all detector effects and all known backgrounds. Comparative results are also shown for particle-level predicitions from ALPGEN, SHERPA and BLACKHAT-SHERPA. A separate link gives the Non-Perturbative and QED correction for each table. Note added (26 JUN 2014): The cross section values reported in Tables 1, 3-25, 51, 53-75 below should be multiplied by a factor of 1.0187 to take into account the updated value of the integrated luminosity for the ATLAS 2010 data taking period. The uncertainty on the global normalisation ("Lumi") increases slightly from 3.4% to 3.5%. See Eur.Phys.J. C73 (2013) 2518 for more details. The predicted W+jets cross section as a function of the invariant mass of the first+second jets for jet multiplicites >= 2 and jet PT > 30 GeV.

CERN-LHC. Measurement of the event-shape cross sections for high-$p_{\textrm{T}}$ multijet production in proton-proton collisions at a centre-of-mass energy of 13 TeV with 139/fb of data collected in Run II. Measured relative cross sections for multijet production as a function of $C$ for $n^{\textrm{jet}}\geq$ 3 and $H_{\textrm{T2}}$ > 2.0 TeV.

CERN-LHC. Measurement of the event-shape cross sections for high-$p_{\textrm{T}}$ multijet production in proton-proton collisions at a centre-of-mass energy of 13 TeV with 139/fb of data collected in Run II. Measured relative cross sections for multijet production as a function of $C$ for $n^{\textrm{jet}}\geq$ 3 and $H_{\textrm{T2}}$ > 2.0 TeV.

CERN-LHC. The distributions of event-by-event harmonic flow coefficients vn for n = 2-4 are measured in sqrt(sNN) = 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 mub^-1 recorded in 2010. The shapes of the vn distributions suggest that the associated flow vectors are described by a two-dimensional Gaussian function in central collisions for v2 and over most of the measured centrality range for v3 and v4. Significant deviations from this function are observed for v2 in mid-central and peripheral collisions, and a small deviation is observed for v3 in mid-central collisions. In order to be sensitive to these deviations, it is shown that the commonly used multi-particle cumulants, involving four particles or more, need to be measured with a precision better than a few percent. The vn 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 vn 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. .

CERN-LHC. The distributions of event-by-event harmonic flow coefficients vn for n = 2-4 are measured in sqrt(sNN) = 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 mub^-1 recorded in 2010. The shapes of the vn distributions suggest that the associated flow vectors are described by a two-dimensional Gaussian function in central collisions for v2 and over most of the measured centrality range for v3 and v4. Significant deviations from this function are observed for v2 in mid-central and peripheral collisions, and a small deviation is observed for v3 in mid-central collisions. In order to be sensitive to these deviations, it is shown that the commonly used multi-particle cumulants, involving four particles or more, need to be measured with a precision better than a few percent. The vn 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 vn 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. .

CERN-LHC. A search for R-parity violating supersymmetry in final states characterised by high jet multiplicity, at least one isolated light lepton and either zero or at least three $b$-tagged jets is presented. The search uses 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data collected by the ATLAS experiment during Run 2 of the Large Hadron Collider. The results are interpreted in the context of R-parity-violating supersymmetry models that feature gluino production, top-squark production, or electroweakino production. The dominant sources of background are estimated using a data-driven model, based on observables at medium jet multiplicity, to predict the $b$-tagged jet multiplicity distribution at the higher jet multiplicities used in the search. Machine learning techniques are used to reach sensitivity to electroweakino production, extending the data-driven background estimation to the shape of the machine learning discriminant. No significant excess over the Standard Model expectation is observed and exclusion limits at the 95% confidence-level are extracted, reaching as high as 2.4 TeV in gluino mass, 1.35 TeV in top-squark mass, and 320 (365) GeV in higgsino (wino) mass. The observed data event yields and the corresponding estimates for the backgrounds in the different $b$-jet multiplicity bins for the 20 GeV jet $p_{\mathrm{T}}$ threshold regions defined for the EWK analysis in the $2\ell^{\mathrm{sc}}$ category for 4 jets. The background is estimated by including all bins in the fit. All uncertainties, which may be correlated across the bins, are included in the total background uncertainty.

CERN-LHC. A search for R-parity violating supersymmetry in final states characterised by high jet multiplicity, at least one isolated light lepton and either zero or at least three $b$-tagged jets is presented. The search uses 139 fb$^{-1}$ of $\sqrt{s} = 13$ TeV proton-proton collision data collected by the ATLAS experiment during Run 2 of the Large Hadron Collider. The results are interpreted in the context of R-parity-violating supersymmetry models that feature gluino production, top-squark production, or electroweakino production. The dominant sources of background are estimated using a data-driven model, based on observables at medium jet multiplicity, to predict the $b$-tagged jet multiplicity distribution at the higher jet multiplicities used in the search. Machine learning techniques are used to reach sensitivity to electroweakino production, extending the data-driven background estimation to the shape of the machine learning discriminant. No significant excess over the Standard Model expectation is observed and exclusion limits at the 95% confidence-level are extracted, reaching as high as 2.4 TeV in gluino mass, 1.35 TeV in top-squark mass, and 320 (365) GeV in higgsino (wino) mass. The observed data event yields and the corresponding estimates for the backgrounds in the different $b$-jet multiplicity bins for the 20 GeV jet $p_{\mathrm{T}}$ threshold regions defined for the EWK analysis in the $2\ell^{\mathrm{sc}}$ category for 4 jets. The background is estimated by including all bins in the fit. All uncertainties, which may be correlated across the bins, are included in the total background uncertainty.

Measurements of the second Fourier harmonic coefficient ($v_2$) of the azimuthal distributions of prompt and nonprompt D$^{0}$ mesons produced in pp and pPb collisions are presented. Nonprompt D$^{0}$ mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, $v_2$ signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum ($p_{\mathrm{T}}$) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D$^{0}$ meson $v_2$ values in pp and pPb collisions are similar in magnitude. The $v_2$ values for open beauty hadrons are extracted for the first time via nonprompt D$^{0}$ mesons in D$^{0}$ collisions. For $p_{\mathrm{T}}$ in the range of 2-5 GeV, the results suggest that $v_2$ for nonprompt D$^{0}$ mesons is smaller than that for prompt D$^{0}$ mesons. These new measurements indicate a positive charm hadron $v_2$ in pp collisions and suggest a mass dependence in $v_2$ between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. Results of elliptic flow, corrected for short range correlations, for prompt neutral D mesons, as a function of multiplicity for $|y_{lab}|< 1$, with 2$ < p_{T} < $4 GeV in pPb collisions at 8.16 TeV.

Measurements of the second Fourier harmonic coefficient ($v_2$) of the azimuthal distributions of prompt and nonprompt D$^{0}$ mesons produced in pp and pPb collisions are presented. Nonprompt D$^{0}$ mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, $v_2$ signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum ($p_{\mathrm{T}}$) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D$^{0}$ meson $v_2$ values in pp and pPb collisions are similar in magnitude. The $v_2$ values for open beauty hadrons are extracted for the first time via nonprompt D$^{0}$ mesons in D$^{0}$ collisions. For $p_{\mathrm{T}}$ in the range of 2-5 GeV, the results suggest that $v_2$ for nonprompt D$^{0}$ mesons is smaller than that for prompt D$^{0}$ mesons. These new measurements indicate a positive charm hadron $v_2$ in pp collisions and suggest a mass dependence in $v_2$ between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. Results of elliptic flow, corrected for short range correlations, for prompt neutral D mesons, as a function of multiplicity for $|y_{lab}|< 1$, with 2$ < p_{T} < $4 GeV in pPb collisions at 8.16 TeV.

CERN-LHC. Inclusive-photon production and its dependence on photon isolation in pp collisions at a centre-of-mass energy of 13 TeV using 139/fb of ATLAS data. The cross sections are measured as functions of the photon transverse energy in different regions of photon pseudorapidity. The photons are required to be isolated by means of a fixed-cone method with two different cone radii (R=0.4 and 0.2). The dependence of the inclusive-photon production on the photon isolation is investigated by measuring the fiducial cross sections as functions of the isolation-cone radius and the ratios of the differential cross sections with different radii in different regions of photon pseudorapidity. The photon is required to have a transverse energy above 250 GeV and absolute value of pseudorapity |etaGamma|<2.37, excluding the region 1.37<|etaGamma|<1.56. The photon isolation is ensured by requiring the transverse energy around a cone of radius R=0.4 (or R=0.2) around the photon to be less than (4.8 + 0.0042 * ETGamma) [GeV]. At particle level it is the sum of transverse energy from all stable particles, except for muons, neutrinos and the photon itself, in a cone of size R =0.4 (or R=0.2) around the photon direction after the contribution from the underlying event is subtracted; the same subtraction procedure, based on the jet-area method, used on data is applied at the particle level (see the journal publication for details). Information about the bin-to-bin correlation of the systematic uncertainties. The following uncertainties are to be treated as uncorrelated bin-to-bin: sysPhotonID, sysBackgroundIsolation, sysBackgroundIsolationUpperLimit, sysBackgroundID, sysIsolationMC and sysMCstats. The systematic uncertainty due to the photon energy scale and resolution is partially correlated bin-to-bin and its decomposition into independent sources is given. In order to take into account properly the correlations due to the photon energy scale and resolution, see the information provided below. The systematic uncertainty due to the photon energy scale (GES) and resolution (GER) is decomposed into 79 independent components: starting from the one labelled RESOLUTION_AF2 until the one labelled PH_SCALE_LEAKAGEUNCONV. Each of the 79 independent components has two variations (up and down). The uncertainties due to the up and down variations for each component are not necessarily symmetric and do not necessarily have different signs. Furthermore, the uncertainty for a given variation (up or down) of a given component can change sign bin to bin in Etgamma. As a result, providing the positive and negative uncertainties as such would mean that the correlation between different Etgamma bins and different measurements is lost. To avoid that loss and to provide the information on the correlation the following format is used for the uncertainties of each independent component in the tables 1 to 12 (for the differential cross sections), tables 25 to 30 (for the ratios of differential cross sections with different isolation radii) and tables 37 to 42 (for the fiducial integrated cross sections): for the upper entry of the uncertainty, the systematic uncertainty of the down variation is given, which can be either positive or negative, and is fully correlated with the upper entries of the other Etgamma bins (for the same component); for the lower entry of the uncertainty, the systematic uncertainty of the up variation is given, which can be either positive or negative, and is fully correlated with the lower entries of the other Etgamma bins (for the same component). For example, for the component labelled SCALE_L2GAIN: the upper entry corresponds to the sistematic uncertainty due to SCALE_L2GAIN__1down and the lower entry corresponds to the sistematic uncertainty due to SCALE_L2GAIN__1up. Predictions for the differential cross sections (tables 13 to 24), ratios (tables 31 to 36) and fiducial integrated cross sections (tables 43 to 48) are given at NNLO QCD from the program NNLOJET using the CT18 PDF set at NNLO; for details, see the journal publication and the reference [19] (X. Chen et al., Single photon production at hadron colliders at NNLO QCD with realistic photon isolation, JHEP 08, 2022, 094). Four sources of uncertainty are considered and quoted separately for each bin in EtGamma, each region of |etaGamma| and each photon isolation radius: the uncertainty due to terms beyond NNLO (TheoryUncertEnvelopeScales), the uncertainty due to that in the PDFs (TheoryUncertPDF), the uncertainty due to that in alphas (TheoryUncertAlphas) and the uncertainty in the non-perturbative corrections (TheoryUncertNonPerturbative). The first one (TheoryUncertEnvelopeScales) was calculated at NNLO using the envelope of the 15-point scheme of variations of the renormalisation, factorisation and fragmentation scales (variations of two or more scales in opposite directions are excluded). The second one (TheoryUncertPDF) was calculated at NLO...

CERN-LHC. Inclusive-photon production and its dependence on photon isolation in pp collisions at a centre-of-mass energy of 13 TeV using 139/fb of ATLAS data. The cross sections are measured as functions of the photon transverse energy in different regions of photon pseudorapidity. The photons are required to be isolated by means of a fixed-cone method with two different cone radii (R=0.4 and 0.2). The dependence of the inclusive-photon production on the photon isolation is investigated by measuring the fiducial cross sections as functions of the isolation-cone radius and the ratios of the differential cross sections with different radii in different regions of photon pseudorapidity. The photon is required to have a transverse energy above 250 GeV and absolute value of pseudorapity |etaGamma|<2.37, excluding the region 1.37<|etaGamma|<1.56. The photon isolation is ensured by requiring the transverse energy around a cone of radius R=0.4 (or R=0.2) around the photon to be less than (4.8 + 0.0042 * ETGamma) [GeV]. At particle level it is the sum of transverse energy from all stable particles, except for muons, neutrinos and the photon itself, in a cone of size R =0.4 (or R=0.2) around the photon direction after the contribution from the underlying event is subtracted; the same subtraction procedure, based on the jet-area method, used on data is applied at the particle level (see the journal publication for details). Information about the bin-to-bin correlation of the systematic uncertainties. The following uncertainties are to be treated as uncorrelated bin-to-bin: sysPhotonID, sysBackgroundIsolation, sysBackgroundIsolationUpperLimit, sysBackgroundID, sysIsolationMC and sysMCstats. The systematic uncertainty due to the photon energy scale and resolution is partially correlated bin-to-bin and its decomposition into independent sources is given. In order to take into account properly the correlations due to the photon energy scale and resolution, see the information provided below. The systematic uncertainty due to the photon energy scale (GES) and resolution (GER) is decomposed into 79 independent components: starting from the one labelled RESOLUTION_AF2 until the one labelled PH_SCALE_LEAKAGEUNCONV. Each of the 79 independent components has two variations (up and down). The uncertainties due to the up and down variations for each component are not necessarily symmetric and do not necessarily have different signs. Furthermore, the uncertainty for a given variation (up or down) of a given component can change sign bin to bin in Etgamma. As a result, providing the positive and negative uncertainties as such would mean that the correlation between different Etgamma bins and different measurements is lost. To avoid that loss and to provide the information on the correlation the following format is used for the uncertainties of each independent component in the tables 1 to 12 (for the differential cross sections), tables 25 to 30 (for the ratios of differential cross sections with different isolation radii) and tables 37 to 42 (for the fiducial integrated cross sections): for the upper entry of the uncertainty, the systematic uncertainty of the down variation is given, which can be either positive or negative, and is fully correlated with the upper entries of the other Etgamma bins (for the same component); for the lower entry of the uncertainty, the systematic uncertainty of the up variation is given, which can be either positive or negative, and is fully correlated with the lower entries of the other Etgamma bins (for the same component). For example, for the component labelled SCALE_L2GAIN: the upper entry corresponds to the sistematic uncertainty due to SCALE_L2GAIN__1down and the lower entry corresponds to the sistematic uncertainty due to SCALE_L2GAIN__1up. Predictions for the differential cross sections (tables 13 to 24), ratios (tables 31 to 36) and fiducial integrated cross sections (tables 43 to 48) are given at NNLO QCD from the program NNLOJET using the CT18 PDF set at NNLO; for details, see the journal publication and the reference [19] (X. Chen et al., Single photon production at hadron colliders at NNLO QCD with realistic photon isolation, JHEP 08, 2022, 094). Four sources of uncertainty are considered and quoted separately for each bin in EtGamma, each region of |etaGamma| and each photon isolation radius: the uncertainty due to terms beyond NNLO (TheoryUncertEnvelopeScales), the uncertainty due to that in the PDFs (TheoryUncertPDF), the uncertainty due to that in alphas (TheoryUncertAlphas) and the uncertainty in the non-perturbative corrections (TheoryUncertNonPerturbative). The first one (TheoryUncertEnvelopeScales) was calculated at NNLO using the envelope of the 15-point scheme of variations of the renormalisation, factorisation and fragmentation scales (variations of two or more scales in opposite directions are excluded). The second one (TheoryUncertPDF) was calculated at NLO...