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Measurement of the $t \bar{t}$ production cross section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96-TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 100 (2008) 192004, 2008.
Inspire Record 781643 DOI 10.17182/hepdata.42684

We measure the ttbar production cross section in ppbar collisions at sqrt{s}=1.96 TeV in the lepton+jets channel. Two complementary methods discriminate between signal and background, b-tagging and a kinematic likelihood discriminant. Based on 0.9 fb-1 of data collected by the D0 detector at the Fermilab Tevatron Collider, we measure sigma_ttbar=7.62+/-0.85 pb, assuming the current world average m_t=172.6 GeV. We compare our cross section measurement with theory predictions to determine a value for the top quark mass of 170+/-7 GeV.

2 data tables match query

The combined result for the TOP TOPBAR production cross section at top quark mass of 175 GeV.. The second DSYS error is the uncertainty on the luminosity.

The cross section for TOP TOPBAR production at the world average top quark mass of 172.6 GeV.. Errors contain both statistics and systematics.


Measurement of the $t \bar{t}$ production cross section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96-TeV using kinematic characteristics of lepton + jets events

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev. D76 (2007) 092007, 2007.
Inspire Record 750966 DOI 10.17182/hepdata.42702

We present a measurement of the top quark pair production cross section in ppbar collisions at sqrt(s)=1.96 TeV utilizing 425 pb-1 of data collected with the D0 detector at the Fermilab Tevatron Collider. We consider the final state of the top quark pair containing one high-pT electron or muon and at least four jets. We exploit specific kinematic features of ttbar events to extract the cross section. For a top quark mass of 175 GeV, we measure sigma_ttbar = 6.4 +1.3-1.2(stat} +/- 0.7(syst)+/- 0.4(lum) pb in good agreement with the standard model prediction.

1 data table match query

TOP TOPBAR production cross section.


Measurement of the $t \bar{t}$ production cross-section in $p \bar{p}$ collisions using dilepton events

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev. D76 (2007) 052006, 2007.
Inspire Record 752236 DOI 10.17182/hepdata.42700

We present a measurement of the ttbar pair production cross section in ppbar collisions at sqrt(s) = 1.96 TeV utilizing approximately 425 pb-1 of data collected with the D0 detector. We consider decay channels containing two high pT charged leptons (either e or \mu) from leptonic decays of both top-daughter W bosons. These were gathered using four sets of selection criteria, three of which required that a pair of fully identified leptons (i.e., e\mu, ee, or \mu\mu) be found. The fourth approach imposed less restrictive criteria on one of the lepton candidates and required that at least one hadronic jet in each event be tagged as containing a b quark. For a top quark mass of 175 GeV, the measured cross section is 7.4 +/-1.4(stat} +/- 1.0(syst) pb.

2 data tables match query

TOP TOPBAR production cross section for top quark mass 175 GeV.

TOP TOPBAR production cross section for the current Tevatron average top quark mass 170.9 GeV.. Error contains both statistics and systematics.


$t \bar{t}$ production cross-section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.8-TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abdesselam, A. ; et al.
Phys.Rev. D67 (2003) 012004, 2003.
Inspire Record 586609 DOI 10.17182/hepdata.54899

Results are presented on a measurement of the ttbar pair production cross section in ppbar collisions at sqrt{s} = 1.8 TeV from nine independent decay channels. The data were collected by the Dzero experiment during the 1992-1996 run of the Fermilab Tevatron Collider. A total of 80 candidate events are observed with an expected background of 38.8 +- 3.3 events. For a top quark mass of 172.1 GeV/c^2, the measured cross section is 5.69 +- 1.21 (stat) +- 1.04 (sys) pb.

1 data table match query

Measured top quark pair production cross section in the different channels and the various averages, including the overall average.


First measurement of $\sigma$ ($p \bar{p} \to Z^{)}$ . Br ($Z \to \tau \tau^{)}$ at $\sqrt{s}$ = 1.96- TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev. D71 (2005) 072004, 2005.
Inspire Record 666357 DOI 10.17182/hepdata.50921

We present a measurement of the cross section for $Z$ production times the branching fraction to $\tau$ leptons, $\sigma \cdot$Br$(Z\to \tau^+ \tau^-)$, in $p \bar p$ collisions at $\sqrt{s}=$1.96 TeV in the channel in which one $\tau$ decays into $\mu \nu_{\mu} \nu_{\tau}$, and the other into $\rm {hadrons} + \nu_{\tau}$ or $e \nu_e \nu_{\tau}$. The data sample corresponds to an integrated luminosity of 226 pb$^{-1}$ collected with the D{\O}detector at the Fermilab Tevatron collider. The final sample contains 2008 candidate events with an estimated background of 55%. From this we obtain $\sigma \cdot$Br$(Z \to \tau^+ \tau^-)=237 \pm 15$(stat)$\pm 18$(sys)$ \pm 15$(lum) pb, in agreement with the standard model prediction.

1 data table match query

Measured cross section times branching ratio.


Jet Production via Strongly-Interacting Color-Singlet Exchange in $p\bar{p}$ Collisions

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 76 (1996) 734-739, 1996.
Inspire Record 400107 DOI 10.17182/hepdata.42348

A study of the particle multiplicity between jets with large rapidity separation has been performed using the D\O\ detector at the Fermilab Tevatron $p\bar{p}$ Collider operating at $\sqrt{s}=1.8$\,TeV. A significant excess of low-multiplicity events is observed above the expectation for color-exchange processes. The measured fractional excess is $1.07 \pm 0.10({\rm stat})~{ + 0.25}_{- 0.13}({\rm syst})\%$, which is consistent with a strongly-interacting color-singlet (colorless) exchange process and cannot be explained by electroweak exchange alone. A lower limit of $0.80\%$ (95\% C.L.) is obtained on the fraction of dijet events with color-singlet exchange, independent of the rapidity gap survival probability.

1 data table match query

'Opposite-side' jets with a large pseudorapidity separation. A cone algorithm with radius R = sqrt(d(etarap)**2+d(phi)**2)=0.7 is used for jet funding. Double negative binomial distribution (NBD) is used to parametrize the color-exchange component of the opposite-side multiplicity distribution betweeb jets. A result of extrapolation to the zero multiplicity point. Quoted systematic error is a result of combining in quadrature of the systematic errors described above.


Model-independent measurement of the $W$ boson helicity in top quark decays at D0

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 100 (2008) 062004, 2008.
Inspire Record 767094 DOI 10.17182/hepdata.47072

We present the first model-independent measurement of the helicity of $W$ bosons produced in top quark decays, based on a 1 fb$^{-1}$ sample of candidate $t\bar{t}$ events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron $p\bar{p}$ Collider. We reconstruct the angle $\theta^*$ between the momenta of the down-type fermion and the top quark in the $W$ boson rest frame for each top quark decay. A fit of the resulting \costheta distribution finds that the fraction of longitudinal $W$ bosons $f_0 = 0.425 \pm 0.166 \hbox{(stat.)} \pm 0.102 \hbox{(syst.)}$ and the fraction of right-handed $W$ bosons $f_+ = 0.119 \pm 0.090 \hbox{(stat.)} \pm 0.053 \hbox{(syst.)}$, which is consistent at the 30% C.L. with the standard model.

6 data tables match query

COS(THETA*) distribution for leptonic W decay in lepton+jets events.. Data are read from plots and errors are statistcial (sqrt(N)).

COS(THETA*) distribution for hadronic W decay in lepton+jets events.. Data are read from plots and errors are statistcial (sqrt(N)).

COS(THETA*) distribution for W decay in dilepton events.. Data are read from plots and errors are statistcial (sqrt(N)).

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A Study of the strong coupling constant using $W + {\rm jets}$ processes

The D0 collaboration Abachi, S. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 75 (1995) 3226-3231, 1995.
Inspire Record 394610 DOI 10.17182/hepdata.42454
1 data table match query

Two values of ALPHA_S corresponds the two different parton distribution functions (pdf) used in extraction of ALPHA_S from the ratio. The dominant systematic error is from the jet energy scale uncertainty.


Measurement of the $t \bar{t}$ production cross section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96-TeV in dilepton final states

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Lett. B626 (2005) 55-64, 2005.
Inspire Record 683416 DOI 10.17182/hepdata.42759

We present a measurement of the top quark pair (ttbar) production cross section in ppbar collisions at a center-of-mass energy of 1.96 TeV using 230 pb-1 of data collected by the DO detector at the Fermilab Tevatron Collider. We select events in the dilepton final states ee, emu and mumu based on kinematical properties consistent with ttbar events. For a top quark mass of 175 GeV, we measure a top pair production cross section sigma(ttbar) = 8.6 +3.2-2.7 (stat) +/-1.1 (syst) +/-0.6 (lumi) pb, in good agreement with the standard model prediction.

1 data table match query

TTBAR production cross section.


Measurement of the $t \bar{t}$ production cross section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96 = TeV using kinematic characteristics of lepton + jets events

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Lett. B626 (2005) 45-54, 2005.
Inspire Record 681233 DOI 10.17182/hepdata.27001

We present a measurement of the top quark pair ttbar production cross section in ppbar collisions at a center-of-mass energy of 1.96 TeV using 230 pb**{-1} of data collected by the DO detector at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), large missing transverse energy, and at least four jets, and extract the ttbar content of the sample based on the kinematic characteristics of the events. For a top quark mass of 175 GeV, we measure sigma(ttbar) = 6.7 {+1.4-1.3} (stat) {+1.6- 1.1} (syst) +/-0.4 (lumi) pb, in good agreement with the standard model prediction.

1 data table match query

TTBAR production cross section from the combined electron+jet and muon+jet channels.


Measurement of the $W W$ production cross section in $p\bar{p}$ collisions at $\sqrt{s} = 1.96$ TeV

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev.Lett. 94 (2005) 151801, 2005.
Inspire Record 662561 DOI 10.17182/hepdata.42037

We present a measurement of the W boson pair-production cross section in p anti-p collisions at a center-of-mass energy of sqrt{s}=1.96 TeV. The data, collected with the Run II DO detector, correspond to an integrated luminosity of 224-252 pb^-1 depending on the final state (ee, emu or mumu). We observe 25 candidates with a background expectation of 8.1+/-0.6(stat)+/-0.6(syst)+/-0.5(lum) events. The probability for an upward fluctuation of the background to produce the observed signal is 2.3x10^-7, equivalent to 5.2 standard deviations.The measurement yields a cross section of 13.8+4.3/-3.8(stat)+1.2/-0.9(syst)+/-0.9(lum) pb, in agreement with predictions from the standard model.

1 data table match query

Total cross section for W boson pair production. The second systematic (DSYS) error is due to the uncertainty in the luminosity.


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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Probing hard color-singlet exchange in $p\bar{p}$ collisions at $\sqrt{s} = 630$ GeV and 1800 GeV

The D0 collaboration Abbott, B. ; Abolins, M. ; Abramov, V. ; et al.
Phys.Lett. B440 (1998) 189-202, 1998.
Inspire Record 476389 DOI 10.17182/hepdata.42131

We present results on dijet production via hard color-singlet exchange in proton-antiproton collisions at root-s = 630 GeV and 1800 GeV using the DZero detector. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, separation in pseudorapidity between the two highest transverse energy jets, and proton-antiproton center-of-mass energy. The results are consistent with a color-singlet fraction that increases with an increasing fraction of quark-initiated processes and inconsistent with two-gluon models for the hard color-singlet.

2 data tables match query

Colour-singlet fraction at 1.8 TeV.

Ratio of colour-singlet fractions between 630 and 1800 GeV.


Measurement of the $t\bar{t}$ cross section using high-multiplicity jet events

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Rev. D82 (2010) 032002, 2010.
Inspire Record 837547 DOI 10.17182/hepdata.52975

We present a measurement of the ttbar cross section using high-multiplicity jet events produced in ppbar collisions at sqrt{s}=1.96 TeV. These data were recorded at the Fermilab Tevatron collider with the D0 detector. Events with at least six jets, two of them identified as b jets, were selected from a 1 fb-1 data set. The measured cross section, assuming a top quark mass of 175 GeV/c^2, is 6.9 \pm 2.0 pb, in agreement with theoretical expectations.

1 data table match query

Measured top topbar cross section at two values of the top mass.


Measurement of the $t \bar{t}$ production cross section in $p \bar{p}$ collisions at $\sqrt{s}$ = 1.96-TeV using lepton + jets events with lifetime $b^-$ tagging

The D0 collaboration Abazov, V.M. ; Abbott, B. ; Abolins, M. ; et al.
Phys.Lett. B626 (2005) 35-44, 2005.
Inspire Record 681605 DOI 10.17182/hepdata.63680

We present a measurement of the top quark pair ($t\bar{t}$) production cross section ($\sigma_{t\bar{t}}$) in $p\bar{p}$ collisions at $\sqrt{s}=1.96$ TeV using 230 pb$^{-1}$ of data collected by the D0 experiment at the Fermilab Tevatron Collider. We select events with one charged lepton (electron or muon), missing transverse energy, and jets in the final state. We employ lifetime-based b-jet identification techniques to further enhance the $t\bar{t}$ purity of the selected sample. For a top quark mass of 175 GeV, we measure $\sigma_{t\bar{t}}=8.6^{+1.6}_{-1.5}(stat.+syst.)\pm 0.6(lumi.)$ pb, in agreement with the standard model expectation.

1 data table match query

TTBAR production cross section. Error contains statistical and systematics (excluding the luminosity uncertainty).


Search for supersymmetry in events with photons, bottom quarks, and missing transverse momentum in proton–proton collisions at a centre-of-mass energy of 7 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Lett. B719 (2013) 261-279, 2013.
Inspire Record 1198427 DOI 10.17182/hepdata.9959
6 data tables match query

Missing ET distribution.

Signal Point Information: (1) Number of Monte Carlo events generated (2) Total signal cross section (pb) (3) Signal acceptance (4) Relative uncertainty on acceptance (5) CLs expected (6) CLs observed.

The observed limit contour in the GLUINO-NEUTRALINO plane.

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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 match query

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 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
No Journal Information, 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.


Search for Supersymmetry in Events with Large Missing Transverse Momentum, Jets, and at Least One Tau Lepton in 7 TeV Proton-Proton Collision Data with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J. C72 (2012) 2215, 2012.
Inspire Record 1189432 DOI 10.17182/hepdata.60276
5 data tables match query

The observed number of signal events as a function of Lambda and Tan(Beta).

The Acceptance, Efficiency and Acceptance x Efficiency for the single tau channel as a function of Lambda and Tan(Beta).

The Acceptance, Efficiency and Acceptance x Efficiency for the two tau channel as a function of Lambda and Tan(Beta).

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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 1501 (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.


Analysis of events with $b$-jets and a pair of leptons of the same charge in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1510 (2015) 150, 2015.
Inspire Record 1361912 DOI 10.17182/hepdata.67661
10 data tables match query

Observed and expected number of events with statistical (first) and systematic (second) uncertainties for the positively charged top pair signal selection. The p-values for agreement between the observed yield and the expected background in each signal region are reported.

Observed and expected number of events with statistical (first) and systematic (second) uncertainties for five of the signal regions defined for VLQ, chiral bprime-quark and four-top-quark production searches. The p-values for agreement between the observed yield and the expected background in each signal region are reported.

Observed and expected number of events with statistical (first) and systematic (second) uncertainties for three of the signal regions defined for VLQ, chiral bprime-quark and four-top-quark production searches. The p-values for agreement between the observed yield and the expected background in each signal region are reported.

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Search for massive, long-lived particles using multitrack displaced vertices or displaced lepton pairs in pp collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D92 (2015) 072004, 2015.
Inspire Record 1362183 DOI 10.17182/hepdata.68777
51 data tables match query

Vertex-level efficiency as a function of the vertex radial position for an RPV SUSY model of squark production with $\tilde{q}\to q[\tilde{\chi}_1^0\to\mu qq]$, where $m(\tilde{q}) = 700$ GeV, $m(\tilde{\chi}_1^0) = 494$ GeV and $c\tau(\tilde{\chi}_1^0)$ = 175 mm. This result is also represented in Figure 3b and Auxiliary Figure 1.

Vertex-level efficiency as a function of the vertex radial position for an RPV SUSY model of squark production with $\tilde{q}\to q[\tilde{\chi}_1^0\to\mu qq]$, where $m(\tilde{q}) = 700$ GeV, $m(\tilde{\chi}_1^0) = 108$ GeV and $c\tau(\tilde{\chi}_1^0)$ = 101 mm.

Vertex-level efficiency as a function of the vertex radial position for an RPV SUSY model of squark production with $\tilde{q}\to q[\tilde{\chi}_1^0\to\mu qb]$, where $m(\tilde{q}) = 700$ GeV, $m(\tilde{\chi}_1^0) = 494$ GeV and $c\tau(\tilde{\chi}_1^0)$ = 175 mm. The other SUSY model point in the figure is tabulated in http://hepdata.cedar.ac.uk/view/ins1362183/d1.

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Search for dark matter in events with a Z boson and missing transverse momentum 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. D90 (2014) 012004, 2014.
Inspire Record 1288061 DOI 10.17182/hepdata.68152

A search is presented for production of dark matter particles recoiling against a leptonically decaying Z boson in 20.3 fb$^{-1}$ of pp collisions at $\sqrt{s}$=8 TeV with the ATLAS detector at the Large Hadron Collider. Events with large missing transverse momentum and two oppositely-charged electrons or muons consistent with the decay of a Z boson are analyzed. No excess above the Standard Model prediction is observed. Limits are set on the mass scale of the contact interaction as a function of the dark matter particle mass using an effective field theory description of the interaction of dark matter with quarks or with Z bosons. Limits are also set on the coupling and mediator mass of a model in which the interaction is mediated by a scalar particle.

6 data tables match query

Summary of the systematic uncertainties for the largest background process (ZZ->llnunu). Statistical uncertaintes are from MC simulation sample size.

Observed yields and expected SM backgrounds in each signal region. Statistical, systematic, and luminosity uncertainteis are added in quadrature to give the total background estimate and uncertainties.

The observed and expected upper limits on the fiducial cross section at 95% C.L. for each signal region.

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Search for metastable heavy charged particles with large ionization energy loss in pp collisions at $\sqrt{s} = 13$ TeV using the ATLAS experiment

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev. D93 (2016) 112015, 2016.
Inspire Record 1448101 DOI 10.17182/hepdata.73584

This paper presents a search for massive charged long-lived particles produced in pp collisions at s=13  TeV at the LHC using the ATLAS experiment. The data set used corresponds to an integrated luminosity of 3.2  fb-1. Many extensions of the Standard Model predict the existence of massive charged long-lived particles, such as R-hadrons. These massive particles are expected to be produced with a velocity significantly below the speed of light, and therefore to have a specific ionization higher than any Standard Model particle of unit charge at high momenta. The Pixel subsystem of the ATLAS detector is used to measure the ionization energy loss of reconstructed charged particles and to search for such highly ionizing particles. The search presented here has much greater sensitivity than a similar search performed using the ATLAS detector in the s=8  TeV data set, thanks to the increase in expected signal cross section due to the higher center-of-mass energy of collisions, to an upgraded detector with a new silicon layer close to the interaction point, and to analysis improvements. No significant deviation from Standard Model background expectations is observed, and lifetime-dependent upper limits on R-hadron production cross sections and masses are set. Gluino R-hadrons with lifetimes above 0.4 ns and decaying to qq¯ plus a 100 GeV neutralino are excluded at the 95% confidence level, with lower mass limit ranging between 740 and 1590 GeV. In the case of stable R-hadrons the lower mass limit at the 95% confidence level is 1570 GeV.

5 data tables match query

Mass distribution for data and expected background for stable particle searches. Also shown are two examples for signals as expected for gluino R-hadrons in the explored mass range. The uncertainty on the background estimation includes both the statistical and systematic uncertainties.

Mass distribution for data and expected background for metastable particle searches. Also shown are two examples for signals as expected for gluino R-hadrons in the explored mass range. The uncertainty on the background estimation includes both the statistical and systematic uncertainties.

Cross-section as a function of mass for gluino R-hadrons with lifetime tau=10 ns, decaying to qanti-q plus a light neutralino of mass=100 GeV. The central value of the observed and expected 95% upper limit on excluded cross-section is given. The 1 sigma band on the expected UL is given as an uncertainty.

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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. B749 (2015) 242-261, 2015.
Inspire Record 1377585 DOI 10.17182/hepdata.69286

This Letter reports a measurement of the exclusive γγ→ℓ+ℓ− ( ℓ=e, μ ) 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 σγγ→e+e−excl.=0.428 ± 0.035 (stat.) ± 0.018 (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 pT>12 GeV and pseudorapidity |η|<2.4 . For muon pairs with invariant mass greater than 20 GeV , muon transverse momentum pT>10 GeV and pseudorapidity |η|<2.4 , the cross-section is determined to be σγγ→μ+μ−excl.=0.628 ± 0.032 (stat.) ± 0.021 (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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