Probing BFKL dynamics in the dijet cross section at large rapidity intervals in $p\bar{p}$ collisions at $\sqrt{s} = 1800$ GeV and 630-GeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Rev.Lett. 84 (2000) 5722-5727, 2000.
Inspire Record 511525 DOI 10.17182/hepdata.41510

Inclusive dijet production at large pseudorapidity intervals (delta_eta) between the two jets has been suggested as a regime for observing BFKL dynamics. We have measured the dijet cross section for large delta_eta in ppbar collisions at sqrt{s}=1800 and 630 GeV using the DO detector. The partonic cross section increases strongly with the size of delta_eta. The observed growth is even stronger than expected on the basis of BFKL resummation in the leading logarithmic approximation. The growth of the partonic cross section can be accommodated with an effective BFKL intercept of a_{BFKL}(20GeV)=1.65+/-0.07.

4 data tables match query

Z(P=3) and Z(P=4) are longitudinal momentum fractions of the proton and antiproton, carried by the two interacting partons: Z(P=3,4) = 2*ET(P=3,4)/SQRT(S)*EXP(+-ETARAP)*COSH(DELTA(ETARAP)/2), where ETARAP = (ETARAP(P=3)+ETARAP(P=4))/2,DELTA(ETARAP) = ABS(ETARAP(P=3)-ETARAP(P=4)).

Z(P=3) and Z(P=4) are longitudinal momentum fractions of the proton and antiproton, carried by the two interacting partons: Z(P=3,4) = 2*ET(P=3,4)/SQRT(S)*EXP(+-ETARAP)*COSH(DELTA(ETARAP)/2), where ETARAP = (ETARAP(P=3)+ETARAP(P=4))/2,DELTA(ETARAP) = ABS(ETARAP(P=3)-ETARAP(P=4)).

Z(P=3) and Z(P=4) are longitudinal momentum fractions of the proton and antiproton, carried by the two interacting partons: Z(P=3,4) = 2*ET(P=3,4)/SQRT(S)*EXP(+-ETARAP)*COSH(DELTA(ETARAP)/2), where ETARAP = (ETARAP(P=3)+ETARAP(P=4))/2,DELTA(ETARAP) = ABS(ETARAP(P=3)-ETARAP(P=4)).

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Measurement of the charged-particle multiplicity inside jets from $\sqrt{s}=8$ TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J.C 76 (2016) 322, 2016.
Inspire Record 1419070 DOI 10.17182/hepdata.72257

The number of charged particles inside jets is a widely used discriminant for identifying the quark or gluon nature of the initiating parton and is sensitive to both the perturbative and non-perturbative components of fragmentation. This paper presents a measurement of the average number of charged particles with $p_\text{T}>500$ MeV inside high-momentum jets in dijet events using 20.3 fb$^{-1}$ of data recorded with the ATLAS detector in $pp$ collisions at $\sqrt{s}=8$ TeV collisions at the LHC. The jets considered have transverse momenta from 50 GeV up to and beyond 1.5 TeV. The reconstructed charged-particle track multiplicity distribution is unfolded to remove distortions from detector effects and the resulting charged-particle multiplicity is compared to several models. Furthermore, quark and gluon jet fractions are used to extract the average charged-particle multiplicity for quark and gluon jets separately.

12 data tables match query

The average charged particle multiplicity for the more forward jet and a charged particle threshold of 0.5 GeV as a function of the jet transverse momentum.

The average charged particle multiplicity for the more forward jet and a charged particle threshold of 2 GeV as a function of the jet transverse momentum.

The average charged particle multiplicity for the more forward jet and a charged particle threshold of 5 GeV as a function of the jet transverse momentum.

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Measurement of four-jet differential cross sections in $\sqrt{s}=8$ TeV proton-proton collisions using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 12 (2015) 105, 2015.
Inspire Record 1394679 DOI 10.17182/hepdata.18620

Differential cross sections for the production of at least four jets have been measured in proton-proton collisions at $\sqrt{s} = 8$ TeV at the Large Hadron Collider using the ATLAS detector. Events are selected if the four anti-$k_{t}$ R=0.4 jets with the largest transverse momentum ($p_{T}$) within the rapidity range $|y|<2.8$ are well separated ($dR^{\rm min}_{4j}>0.65$), all have $p_{T}>64$ GeV, and include at least one jet with $p_{T} >100$ GeV. The dataset corresponds to an integrated luminosity of 20.3 $fb^{-1}$. The cross sections, corrected for detector effects, are compared to leading-order and next-to-leading-order calculations as a function of the jet momenta, invariant masses, minimum and maximum opening angles and other kinematic variables.

46 data tables match query

Measured differential four-jet cross section for R=0.4 jets, in bins of pT1, along with the uncertainties in the measurement. The events are selected using the inclusive analysis cuts. All uncertainties are given in %. The first uncertainty quoted is due to the number of data events. DSYS:mcstat is the statistical uncertainty due to the number of MC simulation events. The other columns, denoted with DSYS, correspond to the experimental systematic uncertainties arising from JES, JER, unfolding and luminosity, respectively.

Measured differential four-jet cross section for R=0.4 jets, in bins of pT2, along with the uncertainties in the measurement. The events are selected using the inclusive analysis cuts. All other details are as for pT1.

Measured differential four-jet cross section for R=0.4 jets, in bins of pT3, along with the uncertainties in the measurement. The events are selected using the inclusive analysis cuts. All other details are as for pT1.

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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 07 (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 match query

$\sqrt{s} = 900$ 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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Measurement of transverse energy-energy correlations in multi-jet events in $pp$ collisions at $\sqrt{s} = 7$ TeV using the ATLAS detector and determination of the strong coupling constant $\alpha_{\mathrm{s}}(m_Z)$

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett.B 750 (2015) 427-447, 2015.
Inspire Record 1387176 DOI 10.17182/hepdata.69306

High transverse momentum jets produced in pp collisions at a centre of mass energy of 7 TeV are used to measure the transverse energy-energy correlation function and its associated azimuthal asymmetry. The data were recorded with the ATLAS detector at the LHC in the year 2011 and correspond to an integrated luminosity of 158 $\mathrm{pb}^{-1}$. The selection criteria demand the average transverse momentum of the two leading jets in an event to be larger than 250 GeV. The data at detector level are well described by Monte Carlo event generators. They are unfolded to the particle level and compared with theoretical calculations at next-to-leading-order accuracy. The agreement between data and theory is good and provides a precision test of perturbative Quantum Chromodynamics at large momentum transfers. From this comparison, the strong coupling constant given at the $Z$ boson mass is determined to be $\alpha_{\mathrm{s}}(m_Z) = 0.1173 \pm 0.0010 \mbox{ (exp.) }^{+0.0065}_{-0.0026} \mbox{ (theo.)}$.

3 data tables match query

Values of the transverse energy-energy correlation function (TEEC).

Values of the asymmetry on the transverse energy-energy correlation function (ATEEC).

Values of the non-perturbative correction factors for the TEEC function derived using Pythia 6 AUET2B.


Measurement of the $WW+WZ$ cross section and limits on anomalous triple gauge couplings using final states with one lepton, missing transverse momentum, and two jets with the ATLAS detector at $\sqrt{\rm{s}} = 7$ TeV

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 01 (2015) 049, 2015.
Inspire Record 1324374 DOI 10.17182/hepdata.66704

The production of a $W$ boson decaying to $e\nu$ or $\mu\nu$ in association with a $W$ or $Z$ boson decaying to two jets is studied using $4.6 \mathrm{fb}^{-1}$ of proton--proton collision data at $\sqrt{\rm{s}} = 7$ TeV recorded with the ATLAS detector at the LHC. The combined $WW+WZ$ cross section is measured with a significance of 3.4$\sigma$ and is found to be $68 \pm 7 \ \mathrm{(stat.)} \pm 19 \ \mathrm{(syst.)} \ pb$, in agreement with the Standard Model expectation of $61.1 \pm 2.2 \ \mathrm{pb}$. The distribution of the transverse momentum of the dijet system is used to set limits on anomalous contributions to the triple gauge coupling vertices and on parameters of an effective-field-theory model.

1 data table match query

The total and fiducial cross sections for the production of W(LEPTON NU) W(JET JET) or W(LEPTON NU) Z(JET JET). The cross sections are the sum of the WW and WZ processes.


Measurement of exclusive $\gamma\gamma\rightarrow \ell^+\ell^-$ production 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.B 749 (2015) 242-261, 2015.
Inspire Record 1377585 DOI 10.17182/hepdata.69286

This Letter reports a measurement of the exclusive $\gamma\gamma\rightarrow \ell^+\ell^- (\ell=e, \mu)$ cross-section in proton-proton collisions at a centre-of-mass energy of 7 TeV by the ATLAS experiment at the LHC, based on an integrated luminosity of $4.6$ fb$^{-1}$. For the electron or muon pairs satisfying exclusive selection criteria, a fit to the dilepton acoplanarity distribution is used to extract the fiducial cross-sections. The cross-section in the electron channel is determined to be $\sigma_{\gamma\gamma\rightarrow e^+e^-}^{\mathrm{excl.}} = 0.428 \pm 0.035 (\mathrm{stat.}) \pm 0.018 (\mathrm{syst.})$ pb for a phase-space region with invariant mass of the electron pairs greater than 24 GeV, in which both electrons have transverse momentum $p_\mathrm{T}>12$ GeV and pseudorapidity $|\eta|<2.4$. For muon pairs with invariant mass greater than 20 GeV, muon transverse momentum $p_\mathrm{T}>10$ GeV and pseudorapidity $|\eta|<2.4$, the cross-section is determined to be $\sigma_{\gamma\gamma\rightarrow \mu^+\mu^- }^{\mathrm{excl.}} = 0.628 \pm 0.032 (\mathrm{stat.}) \pm 0.021 (\mathrm{syst.})$ pb. When proton absorptive effects due to the finite size of the proton are taken into account in the theory calculation, the measured cross-sections are found to be consistent with the theory prediction.

10 data tables match query

Fiducial cross-section SIG for the exclusive e+ e- and mu+ mu- production.

Ratios of the number of observed to the number of expected events based on the MC predictions (R) for the exclusive e+ e- and mu+ mu- production.

Detector response matrix (PROB) for the acoplanarity variable (ACO) for e+ e- channel (empty bins are not reported).

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Search for supersymmetry in events with four or more leptons and missing transverse momentum in pp collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration
Conference Paper, 2012.
Inspire Record 1204218 DOI 10.17182/hepdata.58286

The results of a search for supersymmetric particles in final states with four or more leptons (electrons or muons) and missing transverse momentum with the ATLAS detector are presented. The analysis uses a sample corresponding to an integrated luminosity of 2.06 fb−1 of proton-proton data recorded in 2011 at a centre-of-mass energy of 7 TeV. With an inclusive selection four events are observed, while 1.7±0.9 are expected from Standard Model processes. After applying a Z boson veto for leptons pairs with the same flavour and opposite charge, no events are observed for 0.7±0.8 events expected. Within the selection acceptance, we determine 95% C.L. visible cross-section upper limits for new phenomena of 3.5 fb and 1.5 fb for the selections without and with the Z-veto, respectively.

8 data tables match query

Transverse momentum(energy) distribution of the leading muon(electron) for events with at least 4 leptons each having transverse PT(ET) > 10 GeV.

Transverse momentum(energy) distribution of the second leading muon(electron) for events with at least 4 leptons each having transverse PT(ET) > 10 GeV.

Transverse momentum(energy) distribution of the third leading muon(electron) for events with at least 4 leptons each having transverse PT(ET) > 10 GeV.

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Constraining R-parity violating Minimal Supergravity with stau_1 LSP in a four lepton final state with missing transverse momentum

The ATLAS collaboration
ATLAS-CONF-2012-035, 2012.
Inspire Record 1204284 DOI 10.17182/hepdata.58712

This note describes an interpretation of a search for supersymmetry in final states with at least four isolated leptons (electrons or muons) and missing transverse momentum. The search used 2.06 fb$^{−1}$ of proton-proton collision data collected with the ATLAS experiment, and found no significant excess above expectations from Standard Model processes. Limits are shown for the Minimal Supergravity/Constrained Minimal Supersymmetric Standard Model (mSUGRA/CMSSM) with $m_0=A_0=0$, $\mu>0$ and one $R$-parity violating parameter $\lambda_{121}=0.032$ at the grand unification scale $m_{GUT}$. Keeping these parameters fixed, values of $m_{1/2}<800$ GeV are excluded at 95% CL if tan$\beta < 40$ and $m_{\tilde{\tau}_1}>80$ GeV. These are the first limits from the LHC experiments on a model with a $\tilde{\tau}_1$ as the lightest supersymmetric particle.

9 data tables match query

Observed 95% CL exclusion limit in the m_{1/2}-Tan(Beta) plane.

Expected 95% CL exclusion limit in the m_{1/2}-Tan(Beta) plane.

Observed and Expected CLs values in the m_{1/2}-Tan(Beta) plane Note: lower bound is 0.0001.

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Search for heavy top-like quarks decaying to a Higgs boson and a top quark in the lepton plus jets final state in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration
ATLAS-CONF-2013-018, 2013.
Inspire Record 1229964 DOI 10.17182/hepdata.61326

A search is presented for production of a heavy up-type quark ($t^\prime$) together with its antiparticle, assuming a significant branching ratio for subsequent $t^\prime$ decay into a Standard Model Higgs boson and a top quark, as predicted by vector-like quark models. The search is based on 14.3 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}=8$ TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider. Data are analysed in the lepton+jets final state, characterised by an isolated electron or muon with moderately high transverse momentum, significant missing transverse momentum, and at least six jets. The search exploits the high total transverse momenta of all final state objects and the high multiplicity of $b$ jets characteristic of signal events with at least one Higgs boson decaying into $b\bar{b}$, to discriminate against the dominant background from top quark pair production. No significant excess of events above the Standard Model expectation is observed, and upper limits are derived for vector-like quarks of various masses in the two-dimensional plane of $BR(t^\prime \to Wb)$ versus $BR(t^\prime \to Ht)$, where $H$ is the Standard Model Higgs boson, assumed to have a mass of $125$ GeV. Under the branching ratio assumptions corresponding to a weak-isospin doublet (singlet) scenario, a $t^\prime$ quark with mass lower than 790 (640) GeV is excluded at the 95\% confidence level.

3 data tables match query

The observed and simulated HT distributions in the combined e+jets and mu+jets channels with >=6 jets and 2 b tagged jets.

The observed and simulated HT distributions in the combined e+jets and mu+jets channels with >=6 jets and 3 b tagged jets.

The observed and simulated HT distributions in the combined e+jets and mu+jets channels with >=6 jets and 4 b tagged jets.