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.


Search for dark matter in events with a hadronically decaying W or 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.Lett. 112 (2014) 041802, 2014.
Inspire Record 1254228 DOI 10.17182/hepdata.62353

A search is presented for dark matter pair production in association with a W or Z boson in pp collisions representing 20.3 fb$^{-1}$ of integrated luminosity at $\sqrt{s}$=8 TeV using data recorded with the ATLAS detector at the Large Hadron Collider. Events with a hadronic jet with the jet-mass consistent with a W or Z boson, and with large missing transverse momentum are analyzed. The data are consistent with the Standard Model expectations, and limits are set on the mass scale in effective field theories that describe the interaction of dark matter and Standard Model particles.

6 data tables match query

Distribution of M(jet) in the data and for the predicted background in the top control region (CR) with one muon, one large-radius jet, two narrow jets, at least one b tag, and ETmiss > 250 GeV.

Distribution of M(jet) in the data and for the predicted background in the signal region (SR) with ETmiss > 350 GeV.

Distribution of M(jet) in the data and for the predicted background in the signal region (SR) with ETmiss > 500 GeV.

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Search for supersymmetry in events with four or more leptons in $\sqrt{s}$ = 8 TeV pp collisions with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D90 (2014) 052001, 2014.
Inspire Record 1297226 DOI 10.17182/hepdata.63284
93 data tables match query

The ETmiss distribution in VR0Z.

The effective mass distribution in VR0Z.

The ETmiss distribution in VR2Z.

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Search for long-lived, heavy particles in final states with a muon and multi-track displaced vertex in proton-proton collisions at $\sqrt{s}=7$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Lett. B719 (2013) 280-298, 2013.
Inspire Record 1193933 DOI 10.17182/hepdata.60031
7 data tables match query

Efficiency-vs-radial-vertex-position without re-tracking The efficiency for reconstructing a displaced vertex passing all cuts, as a function of radial distance from the z-axis to the vertex positon. The retrack and noretrack suffixes refer to whether or not the procedure known as re-tracking, where the tracking algorithm is re-run with looser cuts, on the leftover hits from standard tracking, was used to select the tracks that were input to the vertexing algorithm.

Efficiency-vs-radial-vertex-position with re-tracking The efficiency for reconstructing a displaced vertex passing all cuts, as a function of radial distance from the z-axis to the vertex positon. The retrack and noretrack suffixes refer to whether or not the procedure known as re-tracking, where the tracking algorithm is re-run with looser cuts, on the leftover hits from standard tracking, was used to select the tracks that were input to the vertexing algorithm.

Event selection efficiency vs mean proper decay length The MH, HH, ML suffix used for overlaying the graphs refers to the combinations of squark and neutralino masses in the signal MC sample: MH is 700GeV squarks and 494GeV neutralinos, HH is 1.5TeV squarks and 494GeV neutralinos, and ML is 700GeV squarks and 108GeV neutralinos. The tables show the efficiency for reconstructing a signal event, where at least one vertex candidate passes all selection requirements, as a function of the proper decay length c*tau of the neutralino.

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Search for New Particles in Two-Jet Final States in 7 TeV Proton-Proton Collisions with the ATLAS Detector at the LHC

The ATLAS collaboration Aad, G. ; Abbott, B. ; Abdallah, J. ; et al.
Phys.Rev.Lett. 105 (2010) 161801, 2010.
Inspire Record 865423 DOI 10.17182/hepdata.57036
2 data tables match query

The dijet mass distribution (NUMBER OF EVENTS).

95 PCT CL upper limit of the cross section x acceptance.


Search for high-mass resonances decaying to dilepton final states in pp collisions at s**(1/2) = 7-TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
JHEP 1211 (2012) 138, 2012.
Inspire Record 1185259 DOI 10.17182/hepdata.59903
14 data tables match query

Expected and observed number of events in the dielectron channel. The errors quoted include both statistical and systematic uncertainties.

Expected and observed number of events in the dimuon channel. The errors quoted include both statistical and systematic uncertainties.

Observed and predicted dielectron invariant mass (m_ee) distribution in the search region. The bin width is constant in log(m_ee).

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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 using final states with one lepton, jets, and missing transverse momentum with the ATLAS detector in $\sqrt{s}=7$ TeV $pp$

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 106 (2011) 131802, 2011.
Inspire Record 889431 DOI 10.17182/hepdata.57900

This Letter presents the first search for supersymmetry in final states containing one isolated electron or muon, jets, and missing transverse momentum from sqrt{s} = 7 TeV proton-proton collisions at the LHC. The data were recorded by the ATLAS experiment during 2010 and correspond to a total integrated luminosity of 35 pb-1. No excess above the standard model background expectation is observed. Limits are set on the parameters of the minimal supergravity framework, extending previous limits. For A_0 = 0 GeV, tan beta = 3, mu > 0 and for equal squark and gluino masses, gluino masses below 700 GeV are excluded at 95% confidence level.

4 data tables match query

Distribution of ET(C=MISSING) IN GEV for data and background MC calculation.

Distribution of MT IN GEV for data and background MC calculation.

Distribution of M(C=EFFECTIVE) IN GEV for data and background MC calculation.

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Measurement of $Z$ boson Production in Pb+Pb Collisions at $\sqrt{s_{NN}}=2.76$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev.Lett. 110 (2013) 022301, 2013.
Inspire Record 1193044 DOI 10.17182/hepdata.60336
10 data tables match query

The corrected per-event rapidity distribution of Z bosons over the centrality region 0-80%.

The corrected per-event transverse momentum distribution of Z bosons in the centrality region 0-5%.

The corrected per-event transverse momentum distribution of Z bosons in the centrality region 5-10%.

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Search for nonpointing photons in the diphoton and $E^{miss}_T$ final state in $\sqrt{s}$=7  TeV proton-proton collisions using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Phys.Rev. D88 (2013) 012001, 2013.
Inspire Record 1229502 DOI 10.17182/hepdata.61917

A search has been performed for photons originating in the decay of a neutral long-lived particle, exploiting the capabilities of the ATLAS electromagnetic calorimeter to make precise measurements of the flight direction of photons, as well as the calorimeter's excellent time resolution. The search has been made in the diphoton plus missing transverse energy final state, using the full data sample of 4.8/fb of 7 TeV proton-proton collisions collected in 2011 with the ATLAS detector at the LHC. No excess is observed above the background expected from Standard Model processes. The results are used to set exclusion limits in the context of Gauge Mediated Supersymmetry Breaking models, with the lightest neutralino being the next-to-lightest supersymmetric particle and decaying with a lifetime in excess of 0.25 ns into a photon and a gravitino.

3 data tables match query

The 95% CL observed number of signal events vs lifetime for a neutralino with Lambda of 120 TeV together with the SM expectation and the predicition of the SPS8 GMSB model.

The 95% CL observed cross-section vs lifetime for a neutralino with Lambda of 120 TeV together with the SM expectation and the predicition of the SPS8 GMSB model.

The observed exclusion limits on neutralino lifetime as a function of lambda together with the SM expectation.


Search for contact interactions and large extra dimensions in the dilepton channel using proton-proton collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C74 (2014) 3134, 2014.
Inspire Record 1305430 DOI 10.17182/hepdata.65760
10 data tables match query

Reconstructed dielectron mass distributions for data and the SM background estimate.

Reconstructed dimuon mass distributions for data and the SM background estimate.

Reconstructed $\cos\theta^*$ distributions for data and the SM background estimate in the dielectron channel.

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Measurements of the Nuclear Modification Factor for Jets in Pb+Pb Collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV with the ATLAS Detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev.Lett. 114 (2015) 072302, 2015.
Inspire Record 1326911 DOI 10.17182/hepdata.66021

<p>Measurements of inclusive jet production are performed in <inline-formula><mml:math display="inline"><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:math></inline-formula> and <inline-formula><mml:math display="inline"><mml:mi>Pb</mml:mi><mml:mo>+</mml:mo><mml:mi>Pb</mml:mi></mml:math></inline-formula> collisions at <inline-formula><mml:math display="inline"><mml:msqrt><mml:msub><mml:mi>s</mml:mi><mml:mi>NN</mml:mi></mml:msub></mml:msqrt><mml:mo>=</mml:mo><mml:mn>2.76</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>TeV</mml:mi></mml:math></inline-formula> with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 and <inline-formula><mml:math display="inline"><mml:mrow><mml:mn>0.14</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:msup><mml:mrow><mml:mi>nb</mml:mi></mml:mrow><mml:mrow><mml:mo>-</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math></inline-formula>, respectively. The jets are identified with the anti-<inline-formula><mml:math display="inline"><mml:msub><mml:mi>k</mml:mi><mml:mi>t</mml:mi></mml:msub></mml:math></inline-formula> algorithm with <inline-formula><mml:math display="inline"><mml:mi>R</mml:mi><mml:mo>=</mml:mo><mml:mn>0.4</mml:mn></mml:math></inline-formula>, and the spectra are measured over the kinematic range of jet transverse momentum <inline-formula><mml:math display="inline"><mml:mn>32</mml:mn><mml:mo>&lt;</mml:mo><mml:msub><mml:mi>p</mml:mi><mml:mi mathvariant="normal">T</mml:mi></mml:msub><mml:mo>&lt;</mml:mo><mml:mn>500</mml:mn><mml:mtext> </mml:mtext><mml:mtext> </mml:mtext><mml:mi>GeV</mml:mi></mml:math></inline-formula> and absolute rapidity <inline-formula><mml:math display="inline"><mml:mo stretchy="false">|</mml:mo><mml:mi>y</mml:mi><mml:mo stretchy="false">|</mml:mo><mml:mo>&lt;</mml:mo><mml:mn>2.1</mml:mn></mml:math></inline-formula> and as a function of collision centrality. The nuclear modification factor <inline-formula><mml:math display="inline"><mml:msub><mml:mi>R</mml:mi><mml:mi>AA</mml:mi></mml:msub></mml:math></inline-formula> is evaluated, and jets are found to be suppressed by approximately a factor of 2 in central collisions compared to <inline-formula><mml:math display="inline"><mml:mi>p</mml:mi><mml:mi>p</mml:mi></mml:math></inline-formula> collisions. The <inline-formula><mml:math display="inline"><mml:msub><mml:mi>R</mml:mi><mml:mi>AA</mml:mi></mml:msub></mml:math></inline-formula> shows a slight increase with <inline-formula><mml:math display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi mathvariant="italic">T</mml:mi></mml:mrow></mml:msub></mml:mrow></mml:math></inline-formula> and no significant variation with rapidity.</p>

46 data tables match query

The $\langle T_{\mathrm{AA}} \rangle $ and $\langle N_{\mathrm{part}} \rangle$ values and their uncertainties in each centrality bin.

No description provided.

No description provided.

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Search for heavy long-lived multi-charged particles in pp collisions at $\sqrt{s}=\;8$  TeV using the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C75 (2015) 362, 2015.
Inspire Record 1360282 DOI 10.17182/hepdata.67348
3 data tables match query

The observed event yield in data in the B region, the probability $f$ to find a particle above the respective $S$(MDT dE/dx) value before tight selection and the expected background yield in the signal region D with its statistical uncertainty. The last column shows the observed event yield in the D region.

Fractions of signal events (in %) with at least one multi-charged particle, which satisfy the given requirements. The uncertainties quoted are statistical.

Overview of separate contributions (in %) to the systematic uncertainty on the signal. The total uncertainty is given by the quadratic sum of the individual uncertainties.


Search for new particles in events with one lepton and missing transverse momentum in $pp$ collisions at $\sqrt{s}$ = 8 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1409 (2014) 037, 2014.
Inspire Record 1308524 DOI 10.17182/hepdata.65524

This paper presents a search for new particles in events with one lepton (electron or muon) and missing transverse momentum using 20.3 $fb^{-1}$ of proton-proton collision data at $\sqrt{s}=8$ TeV recorded by the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. A $W'$ with Sequential Standard Model couplings is excluded at the 95% confidence level for masses up to 3.24 TeV. Excited chiral bosons ($W^{*}$) with equivalent coupling strengths are excluded for masses up to 3.21 TeV. In the framework of an effective field theory limits are also set on the dark matter-nucleon scattering cross-section as well as the mass scale $M_{*}$ of the unknown mediating interaction for dark matter pair production in association with a leptonically decaying $W$.

19 data tables match query

Spectrum of lepton PT for the electron channel after the event selection. The spectrum is shown with the requirement MT > 252 GeV.

Spectrum of lepton PT for the muon channel after the event selection. The spectrum is shown with the requirement MT > 252 GeV.

Spectrum of ETmiss for the electron channel after the event selection. The spectrum is shown with the requirement MT > 252 GeV.

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Measurement of the production and lepton charge asymmetry of $W$ bosons in Pb+Pb collisions at $\mathbf {\sqrt{\mathbf {s}_{\mathrm {\mathbf {NN}}}}=2.76\;TeV}$ with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C75 (2015) 23, 2015.
Inspire Record 1311623 DOI 10.17182/hepdata.66358
5 data tables match query

Ratio of W+ and W- candidates in $W\rightarrow \ell \nu_{\ell}$ as a function of the mean number of participants $N_{part}$.

$W^\pm$ boson production yield per binary collision as a function of the mean number of participants $N_{part}$.

Differential production yield per binary collision for $W^{+}$ bosons as a function of $|\eta_\ell|$.

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Search for resonant diboson production in the $\mathrm {\ell \ell }q\bar{q}$ final state in $pp$ collisions at $\sqrt{s} = 8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Eur.Phys.J. C75 (2015) 69, 2015.
Inspire Record 1318483 DOI 10.17182/hepdata.66539
3 data tables match query

1D histogram with combined statistical and systematic errors representing the event yields as a function of the reconstructed M(lljj) for the LR (low-pt resolved signal region) and HR (high-pt resolved signal region) and M(llJ) for the MR (merged signal region). system. The value of mass on the x axis is given for the lower edge of the bin.

The theoretical cross section, the expected upper limit, and observed upper limit for the Kaluza Klein graviton signal mass points studied.

The theoretical cross section, the expected upper limit, and observed upper limit for the SSM W-prime signal mass point studied.


Search for new phenomena in the dijet mass distribution using $p-p$ collision data at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Rev. D91 (2015) 052007, 2015.
Inspire Record 1305096 DOI 10.17182/hepdata.66572
14 data tables match query

The reconstructed dijet mass distribution (observed) fitted with a smooth functional form (expected) of 4-parameter or 5-parameter.

Dijet mass resolution obtained from fully simulated PYTHIA QCD Monte Carlo PYTHIA 8.175 [43], with the AU2 tune obtained from ATLAS data [45].

Total cross sections, branching ratios in qg only and acceptances for qg, qgamma, qW, qZ decays (A) for the q* model.

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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 a Heavy Neutral Particle Decaying to $e\mu$, $e\tau$, or $\mu\tau$ 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.Lett. 115 (2015) 031801, 2015.
Inspire Record 1352821 DOI 10.17182/hepdata.68482
24 data tables match query

Observed and predicted $e\mu$ invariant mass distributions.

The expected invariant mass distribution of signal Z'@0.75TeV and $\tilde{\nu}_{\tau}$@1TeV. The arbitrary choice of couplings are: $\lambda_{311}^{'}=0.11$ and $\lambda_{i3k}=0.07$ for $\tilde{\nu}_{\tau}$, $Q_{ll^{'}}=1$ for Z' .

Observed and predicted $e\tau$ invariant mass distributions.

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A search for high-mass resonances decaying to $\tau^{+}\tau^{-}$ in $pp$ collisions at $\sqrt{s}=8$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1507 (2015) 157, 2015.
Inspire Record 1346398 DOI 10.17182/hepdata.68362

A search for high-mass resonances decaying into τ$^{+}$ τ$^{−}$ final states using proton-proton collisions at $ \sqrt{s}=8 $ TeV produced by the Large Hadron Collider is presented. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 19.5–20.3 fb$^{−1}$. No statistically significant excess above the Standard Model expectation is observed, 95% credibility upper limits are set on the cross section times branching fraction of Z′ resonances decaying into τ$^{+}$ τ$^{−}$ pairs as a function of the resonance mass. As a result, Z′ bosons of the Sequential Standard Model with masses less than 2.02 TeV are excluded at 95% credibility. The impact of the fermionic couplings on the Z′ acceptance is investigated and limits are also placed on a Z′ model that exhibits enhanced couplings to third-generation fermions.

9 data tables match query

Signal acceptance times efficiency (ACC*EFF) for Z'L, Z'R, Z'narrow and Z'wide divided by ACC*EFF for Z'SSM as a function of the Z' mass, separately for the had-had and lep-had channels.

Ratio of the Z'NU to Z'SSM cross section times tau+tau- branching fraction (SIG*BR) as a function of sin^2phi and the Z' mass.

Ratio of the Z'NU to Z'SSM acceptance times efficiency (ACC*EFF) in the had-had channel as a function of sin^2phi and the Z' mass.

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A search for $ t\overline{t} $ resonances using lepton-plus-jets events in proton-proton collisions at $ \sqrt{s}=8 $ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
JHEP 1508 (2015) 148, 2015.
Inspire Record 1373299 DOI 10.17182/hepdata.70548

A search for new particles that decay into top quark pairs is reported. The search is performed with the ATLAS experiment at the LHC using an integrated luminosity of 20.3 fb$^{−1}$ of proton-proton collision data collected at a centre-of-mass energy of $ \sqrt{s}=8 $ TeV. The lepton-plus-jets final state is used, where the top pair decays to $ {W}^{+}b{W}^{-}\overline{b} $ , with one W boson decaying leptonically and the other hadronically. The invariant mass spectrum of top quark pairs is examined for local excesses or deficits that are inconsistent with the Standard Model predictions. No evidence for a top quark pair resonance is found, and 95% confidence-level limits on the production rate are determined for massive states in benchmark models. The upper limits on the cross-section times branching ratio of a narrow Z′ boson decaying to top pairs range from 4.2 pb to 0.03 pb for resonance masses from 0.4 TeV to 3.0 TeV. A narrow leptophobic topcolour Z′ boson with mass below 1.8 TeV is excluded. Upper limits are set on the cross-section times branching ratio for a broad colour-octet resonance with Γ/m = 15% decaying to $ t\overline{t} $ . These range from 4.8 pb to 0.03 pb for masses from 0.4 TeV to 3.0 TeV. A Kaluza-Klein excitation of the gluon in a Randall-Sundrum model is excluded for masses below 2.2 TeV.

16 data tables match query

Selection efficiency x Acceptance for a Z' resonance.

Selection efficiency x Acceptance for a KK gluon resonance.

Selection efficiency x Acceptance for a KK graviton resonance.

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Search for scalar leptoquarks in pp collisions at $\sqrt{s}$ = 13 TeV with the ATLAS experiment

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
New J.Phys. 18 (2016) 093016, 2016.
Inspire Record 1462258 DOI 10.17182/hepdata.73322
4 data tables match query

Normalisation factors for the main backgrounds obtained from the combined fit in each of the channels. The total uncertainty is given.

Search for the first generation leptoquarks (LQs). Event yields in the Z control region (CR), ttbar CR and in the signal region (SR). Each CR is treated as one bin in the profile likelihood fit. The SR is split to 7 bins according to $m_{\text{LQ}}^{\text{min}}$ for the fit. The table below shows the total number of events in each CR. For the SR, it shows the number of events per 100 GeV as a function of $m_{\text{LQ}}^{\text{min}}$. The background expectations are scaled by a scale factor extracted from the fit. However, the uncertainties shown are the pre-fit ones. The data event yield uncertainty is statistical (gaussian). The background uncertainty consists of all the experimental and theoretical components summed in quadrature. The uncertainty of the fit-extracted background scale factor is also added in quadrature.

Search for the second generation leptoquarks (LQs). Event yields in the Z control region (CR), ttbar CR and in the signal region (SR). Each CR is treated as one bin in the profile likelihood fit. The SR is split to 7 bins according to $m_{\text{LQ}}^{\text{min}}$ for the fit. The table below shows the total number of events in each CR. For the SR, it shows the number of events per 100 GeV as a function of $m_{\text{LQ}}^{\text{min}}$. The background expectations are scaled by a scale factor extracted from the fit. However, the uncertainties shown are the pre-fit ones. The data event yield uncertainty is statistical (gaussian). The background uncertainty consists of all the experimental and theoretical components summed in quadrature. The uncertainty of the fit-extracted background scale factor is also added in quadrature.

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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.

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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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Version 2
Search for long-lived, massive particles in events with displaced vertices and missing transverse momentum in $\sqrt{s}$ = 13 TeV $pp$ collisions with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1630632 DOI 10.17182/hepdata.78697

A search for long-lived, massive particles predicted by many theories beyond the Standard Model is presented. The search targets final states with large missing transverse momentum and at least one high-mass displaced vertex with five or more tracks, and uses 32.8 fb$^{-1}$ of $\sqrt{s}$ = 13 TeV $pp$ collision data collected by the ATLAS detector at the LHC. The observed yield is consistent with the expected background. The results are used to extract 95\% CL exclusion limits on the production of long-lived gluinos with masses up to 2.37 TeV and lifetimes of $\mathcal{O}(10^{-2})$-$\mathcal{O}(10)$ ns in a simplified model inspired by Split Supersymmetry.

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Parameterized vertex level efficiencies as a function of number of particles associated to a truth decay vertex, and the vertex invariant mass for truth decays with $4$ mm $< R_{\mathrm{decay}} < 22$ mm. Selected particles are required to have nonzero electric charge, $p_{T}(|Q|=1) > 1$ GeV, and $d_0 > 2$ mm. The per-vertex efficiency is evaluated only for truth vertices that have at least 5 associated tracks, an invariant mass $> 10$ GeV, and are in the region $4$ mm $< R_{\mathrm{decay}} < 300$ mm, and $|Z_{\mathrm{decay}}| < 300$ mm. A truth vertex satisfies the vertex level efficiency if it can be matched to a reconstructed DV which passes the final vertex selection.

Parameterized vertex level efficiencies as a function of number of particles associated to a truth decay vertex, and the vertex invariant mass for truth decays with $22$ mm $< R_{\mathrm{decay}} < 25$ mm. Selected particles are required to have nonzero electric charge, $p_{T}(|Q|=1) > 1$ GeV, and $d_0 > 2$ mm. The per-vertex efficiency is evaluated only for truth vertices that have at least 5 associated tracks, an invariant mass $> 10$ GeV, and are in the region $4$ mm $< R_{\mathrm{decay}} < 300$ mm, and $|Z_{\mathrm{decay}}| < 300$ mm. A truth vertex satisfies the vertex level efficiency if it can be matched to a reconstructed DV which passes the final vertex selection.

Vertex reconstruction efficiency as a function of radial position $R$ with and without the special LRT processing for one $R$-hadron signal sample with $m_{\tilde{g}} = 1.2$ TeV, $m_{\tilde{\chi}_{1}^{0}} = 100$ GeV and $\tau_{\tilde{g}} = 1$ ns. The efficiency is defined as the probability for a true LLP decay to be matched with a reconstructed DV fulfilling the vertex preselection criteria in events with a reconstructed primary vertex.

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