Search for additional heavy neutral Higgs and gauge bosons in the ditau final state produced in 36 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1624690 DOI 10.17182/hepdata.78402

A search for heavy neutral Higgs bosons and $Z^{\prime}$ bosons is performed using a data sample corresponding to an integrated luminosity of 36.1 fb$^{-1}$ from proton-proton collisions at $\sqrt{s}$ = 13 TeV recorded by the ATLAS detector at the LHC during 2015 and 2016. The heavy resonance is assumed to decay to $\tau^+\tau^-$ with at least one tau lepton decaying to final states with hadrons and a neutrino. The search is performed in the mass range of 0.2-2.25 TeV for Higgs bosons and 0.2-4.0 TeV for $Z^{\prime}$ bosons. The data are in good agreement with the background predicted by the Standard Model. The results are interpreted in benchmark scenarios. In the context of the hMSSM scenario, the data exclude $\tan\beta > 1.0$ for $m_A$ = 0.25 TeV and $\tan\beta > 42$ for $m_A$ = 1.5 TeV at the 95% confidence level. For the Sequential Standard Model, $Z^{\prime}_\mathrm{SSM}$ with $m_{Z^{\prime}} < 2.42$ TeV is excluded at 95% confidence level, while $Z^{\prime}_\mathrm{NU}$ with $m_{Z^{\prime}} < 2.25$ TeV is excluded for the non-universal $G(221)$ model that exhibits enhanced couplings to third-generation fermions.

29 data tables

Observed and predicted mTtot distribution in the b-veto category of the 1l1tau_h channel. Despite listing this as an exclusive final state (as there must be no b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. In the paper, the first bin is cut off at 60 GeV for aesthetics but contains underflows down to 50 GeV as in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.

Observed and predicted mTtot distribution in the b-tag category of the 1l1tau_h channel. Despite listing this as an exclusive final state (as there must be at least one b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. In the paper, the first bin is cut off at 60 GeV for aesthetics but contains underflows down to 50 GeV as in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.

Observed and predicted mTtot distribution in the b-veto category of the 2tau_h channel. Despite listing this as an exclusive final state (as there must be no b-jets), there is no explicit selection on the presence of additional light-flavour jets. Please note that the bin content is divided by the bin width in the paper figure, but not in the HepData table. The last bin includes overflows. The combined prediction for A and H bosons with masses of 300, 500 and 800 GeV and $\tan\beta$ = 10 in the hMSSM scenario are also provided.

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Searches for heavy $ZZ$ and $ZW$ resonances in the $\ell\ell qq$ and $\nu\nu qq$ final states in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1620910 DOI 10.17182/hepdata.78550

This paper reports searches for heavy resonances decaying into $ZZ$ or $ZW$ using data from proton--proton collisions at a centre-of-mass energy of $\sqrt{s}=13$ TeV. The data, corresponding to an integrated luminosity of 36.1 fb$^{-1}$, were recorded with the ATLAS detector in 2015 and 2016 at the Large Hadron Collider. The searches are performed in final states in which one $Z$ boson decays into either a pair of light charged leptons (electrons and muons) or a pair of neutrinos, and the associated $W$ boson or the other $Z$ boson decays hadronically. No evidence of the production of heavy resonances is observed. Upper bounds on the production cross sections of heavy resonances times their decay branching ratios to $ZZ$ or $ZW$ are derived in the mass range 300--5000 GeV within the context of Standard Model extensions with additional Higgs bosons, a heavy vector triplet or warped extra dimensions. Production through gluon--gluon fusion, Drell--Yan or vector-boson fusion are considered, depending on the assumed model.

16 data tables

Selection acceptance times efficiency for ggF H -> Z Z -> llqq as a function of the Higgs boson mass, combining the HP and LP signal regions of the ZV -> llJ selection and the b-tagged and untagged regions of the ZV -> lljj selection.

Selection acceptance times efficiency for VBF H -> Z Z -> llqq as a function of the Higgs boson mass, combining the HP and LP signal regions of the ZV -> llJ selection and the b-tagged and untagged regions of the ZV -> lljj selection.

Selection acceptance times efficiency for ggF H -> Z Z -> vvqq as a function of the Higgs boson mass, combining the HP and LP signal regions.

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Search for supersymmetry in events with $b$-tagged jets and missing transverse momentum in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1620694 DOI 10.17182/hepdata.79165

A search for the supersymmetric partners of the Standard Model bottom and top quarks is presented. The search uses 36.1 fb$^{-1}$ of $pp$ collision data at $\sqrt{s}=13$ TeV collected by the ATLAS experiment at the Large Hadron Collider. Direct production of pairs of bottom and top squarks ($\tilde{b}_{1}$ and $\tilde{t}_{1}$) is searched for in final states with $b$-tagged jets and missing transverse momentum. Distinctive selections are defined with either no charged leptons (electrons or muons) in the final state, or one charged lepton. The zero-lepton selection targets models in which the $\tilde{b}_{1}$ is the lightest squark and decays via $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$, where $\tilde{\chi}^{0}_{1}$ is the lightest neutralino. The one-lepton final state targets models where bottom or top squarks are produced and can decay into multiple channels, $\tilde{b}_{1} \rightarrow b \tilde{\chi}^{0}_{1}$ and $\tilde{b}_{1} \rightarrow t \tilde{\chi}^{\pm}_{1}$, or $\tilde{t}_{1} \rightarrow t \tilde{\chi}^{0}_{1}$ and $\tilde{t}_{1} \rightarrow b \tilde{\chi}^{\pm}_{1}$, where $\tilde{\chi}^{\pm}_{1}$ is the lightest chargino and the mass difference $m_{\tilde{\chi}^{\pm}_{1}}- m_{\tilde{\chi}^{0}_{1}}$ is set to 1 GeV. No excess above the expected Standard Model background is observed. Exclusion limits at 95\% confidence level on the mass of third-generation squarks are derived in various supersymmetry-inspired simplified models.

101 data tables

Expected exclusion limit for b0L-SRA350 for sbottom pair production with symmetric decay into a bottom quark and a neutralino.

Signal acceptance (in %) in the ( M(SBOTTOM), M(NEUTRALINO) ) mass plane for the symmetric decay of the sbottom into bottom quark and neutralino, for the b0L-SRA350 signal region.

b1L signal region with best expected exclusion limit in the ( M(SBOTTOM), M(NEUTRALINO) ) mass plane for the asymmetric decay of the sbottom into bottom quark and neutralino or top quark and chargino.

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Search for squarks and gluinos in events with an isolated lepton, jets and missing transverse momentum at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1620206 DOI 10.17182/hepdata.78218

The results of a search for squarks and gluinos in final states with an isolated electron or muon, multiple jets and large missing transverse momentum using proton--proton collision data at a center-of-mass energy of $\sqrt{s}$ = 13 TeV are presented. The dataset used was recorded during 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 $fb^{-1}$. No significant excess beyond the expected background is found. Exclusion limits at 95% confidence level are set in a number of supersymmetric scenarios, reaching masses up to 2.1 TeV for gluino pair production and up to 1.25 TeV for squark pair production.

71 data tables

Observed 95% CL exclusion contours for the gluino one-step x = 1/2 model.

Observed upper limits on the signal cross-section for gluino one-step x = 1/2 model.

Efficiency in 2J discovery signal region for gluino one-step x = 1/2 model.

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Search for the direct production of charginos and neutralinos 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 1620202 DOI 10.17182/hepdata.78377

A search for the direct production of charginos and neutralinos in final states with at least two hadronically decaying tau leptons is presented. The analysis uses a dataset of $pp$ collisions corresponding to an integrated luminosity of 36.1 fb$^{-1}$, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of $\sqrt{s}=$ 13 TeV. No significant deviation from the Standard Model background expectation is observed. Limits are derived in scenarios of $\tilde{\chi}_{1}^{+}\tilde{\chi}_{1}^{-}$ pair production and of $\tilde{\chi}_{1}^{\pm}\tilde{\chi}_{2}^{0}$ and $\tilde{\chi}_{1}^{+}\tilde{\chi}_{1}^{-}$ production. Chargino masses up to 630 GeV are excluded at 95\% confidence level in the scenario of direct production of $\tilde{\chi}_{1}^{+}\tilde{\chi}_{1}^{-}$ for a massless $\tilde{\chi}_{1}^{0}$. Common $\tilde{\chi}_{1}^{\pm}$, $\tilde{\chi}_{2}^{0}$ masses up to 760 GeV are excluded in the case of production of $\tilde{\chi}_{1}^{\pm}\tilde{\chi}_{2}^{0}$ and $\tilde{\chi}_{1}^{+}\tilde{\chi}_{1}^{-}$ assuming a massless $\tilde{\chi}_{1}^{0}$.

37 data tables

Observed exclusion contours in chargino pair production model.

Expected exclusion contours in chargino pair production model.

The $E_{\mathrm T}^{\mathrm{miss}}$ distribution in the $W$-CR region. The SM backgrounds other than multi-jet production are estimated from MC simulation. The contribution of $W$+jets events is scaled to the fit result. The multi-jet contribution is estimated from data using the OS-SS method. The hatched bands represent the combined statistical and systematic uncertainties of the total SM background. For illustration, the distributions of the SUSY reference points are also shown as dashed lines. The lower panels show the ratio of data to the SM background estimate. The last bin includes the overflow events.

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Search for direct top squark pair production in final states with two leptons 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 1615470 DOI 10.17182/hepdata.78219

The results of a search for direct pair production of top squarks in events with two opposite-charge leptons (electrons or muons) are reported, using 36.1 fb$^{-1}$ of integrated luminosity from proton--proton collisions at $\sqrt{s}=13$ TeV collected by the ATLAS detector at the Large Hadron Collider. To cover a range of mass differences between the top squark $\tilde{t}$ and lighter supersymmetric particles, four possible decay modes of the top squark are targeted with dedicated selections: the decay $\tilde{t} \rightarrow b \tilde{\chi}_{1}^{\pm}$ into a $b$-quark and the lightest chargino with $\tilde{\chi}_{1}^{\pm} \rightarrow W \tilde{\chi}_{1}^{0}$, the decay $\tilde{t} \rightarrow t \tilde{\chi}_{1}^{0}$ into an on-shell top quark and the lightest neutralino, the three-body decay $\tilde{t} \rightarrow b W \tilde{\chi}_{1}^{0}$ and the four-body decay $\tilde{t} \rightarrow b \ell \nu \tilde{\chi}_{1}^{0}$. No significant excess of events is observed above the Standard Model background for any selection, and limits on top squarks are set as a function of the $\tilde{t}$ and $\tilde{\chi}_{1}^{0}$ masses. The results exclude at 95% confidence level $\tilde{\chi}_{1}^{0}$ masses up to about 720 GeV, extending the exclusion region of supersymmetric parameter space covered by previous searches.

100 data tables

Observed exclusion limits at 95% CL for a simplified model assuming $\tilde{t}_{1}$ pair production, decaying via $\tilde{t}_{1}\rightarrow t+\tilde{\chi}_{1}^{0}$ with 100% branching ratio.

Two-body selection distributions of $m_{T2}^{ll}$ for events satisfying the selection criteria of the six SRs, except for the one on $m_{T2}^{ll}$, after the background fit. The contributions from all SM backgrounds are shown as a histogram stack; the bands represent the total statistical and systematic uncertainty. The rightmost bin of each plot includes overflow events. Reference top squark pair production signal models are overlayed for comparison. Red arrows indicate the signal region selection criteria.

Two-body selection distribution of $n_{jets}$ in CR$^{2-body}_{top}$ after the background fits. The contributions from all SM backgrounds are shown as a histogram stack; the bands represent the total statistical and detector-related systematic uncertainty. The rightmost bin of each plot includes overflow events.

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Search for new phenomena with large jet multiplicities and missing transverse momentum using large-radius jets and flavour-tagging at ATLAS in 13 TeV $pp$ collisions

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1615205 DOI 10.17182/hepdata.77893

A search is presented for particles that decay producing a large jet multiplicity and invisible particles. The event selection applies a veto on the presence of isolated electrons or muons and additional requirements on the number of b-tagged jets and the scalar sum of masses of large-radius jets. Having explored the full ATLAS 2015-2016 dataset of LHC proton-proton collisions at $\sqrt{s}=13~\mathrm{TeV}$, which corresponds to 36.1 fb$^{-1}$ of integrated luminosity, no evidence is found for physics beyond the Standard Model. The results are interpreted in the context of simplified models inspired by R-parity-conserving and R-parity-violating supersymmetry, where gluinos are pair-produced. More generic models within the phenomenological minimal supersymmetric Standard Model are also considered.

126 data tables

Observed 95% CL limit for the pMSSM grid.

$E_{\mathrm{T}}^{\mathrm{miss}} / \sqrt{H_{\mathrm{T}}}$ distribution in signal region SR-8j50-0b. Two benchmark signal models are overlaid on the plot for comparison. Labelled `pMSSM' and `2-step', they show signal distributions from the example SUSY models (as described in the paper): a pMSSM slice model with ($m \tilde{g}$, $m \tilde{\chi_{1}^{\pm}}$) = (1300, 200) GeV and a cascade decay model with ($m \tilde{g}$, $m \tilde{\chi_{1}^{0}}$) = (1300, 200) GeV.

The best-expected signal region and the corresponding best-observed and best-expected CLs values for the 2Step grid.

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Search for heavy resonances decaying to a $W$ or $Z$ boson and a Higgs boson in the $q\bar{q}^{(\prime)}b\bar{b}$ final state in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1611039 DOI 10.17182/hepdata.77272

A search for heavy resonances decaying to a $W$ or $Z$ boson and a Higgs boson in the $q\bar{q}^{(\prime)}b\bar{b}$ final state is described. The search uses 36.1 fb$^{-1}$ of proton-proton collision data at $\sqrt{s} =$ 13 TeV collected by the ATLAS detector at the CERN Large Hadron Collider in 2015 and 2016. The data are in agreement with the Standard Model expectations, with the largest excess found at a resonance mass of 3.0 TeV with a local (global) significance of 3.3 (2.1) $\sigma$. The results are presented in terms of constraints on a simplified model with a heavy vector triplet. Upper limits are set on the production cross-section times branching ratio for resonances decaying to a $W$ ($Z$) boson and a Higgs boson, itself decaying to $b\bar{b}$, in the mass range between 1.1 and 3.8 TeV; the limits range between 83 and 1.6 fb (77 and 1.1 fb) at 95% confidence level.

3 data tables

The observed and expected cross-section upper limits at the 95% confidence level for pp -> V prime -> VH -> qq(bb+cc) in the WH signal region.

The observed and expected cross-section upper limits at the 95% confidence level for pp -> V prime -> VH -> qq(bb+cc) in the ZH signal region.

Signal acceptance x efficiency as a function of resonance mass.


Measurement of detector-corrected observables sensitive to the anomalous production of events with jets and large missing transverse momentum in $pp$ collisions at $\sqrt{s} = 13$ TeV using the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1609448 DOI 10.17182/hepdata.78366

Observables sensitive to the anomalous production of events containing hadronic jets and missing momentum in the plane transverse to the proton beams at the Large Hadron Collider are presented. The observables are defined as a ratio of cross sections, for events containing jets and large missing transverse momentum to events containing jets and a pair of charged leptons from the decay of a $Z/\gamma^\ast$ boson. This definition minimises experimental and theoretical systematic uncertainties in the measurements. This ratio is measured differentially with respect to a number of kinematic properties of the hadronic system in two phase-space regions; one inclusive single-jet region and one region sensitive to vector-boson-fusion topologies. The data are found to be in agreement with the Standard Model predictions and used to constrain a variety of theoretical models for dark-matter production, including simplified models, effective field theory models, and invisible decays of the Higgs boson. The measurements use 3.2 fb$^{-1}$ of proton--proton collision data recorded by the ATLAS experiment at a centre-of-mass energy of 13 TeV and are fully corrected for detector effects, meaning that the data can be used to constrain new-physics models beyond those shown in this paper.

7 data tables

Measured and expected $R^\text{miss}$ as a function of $p_\text{T}^\text{miss}$ in the $\geq 1$ jet phase space. The fiducial SM predictions for the numerator and the denominator are also given.

Measured and expected $R^\text{miss}$ as a function of $p_\text{T}^\text{miss}$ in the VBF jet phase space. The fiducial SM predictions for the numerator and the denominator are also given.

Measured and expected $R^\text{miss}$ as a function of $M_\text{jj}$ in the VBF jet phase space. The fiducial SM predictions for the numerator and the denominator are also given.

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Search for pair production of heavy vector-like quarks decaying to high-$p_{mathrm{T}}$ $W$ bosons and $b$ quarks in the lepton-plus-jets final state in $pp$ collisions at $\sqrt{s}$=13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1609451 DOI 10.17182/hepdata.77271

A search is presented for the pair production of heavy vector-like $T$ and $B$ quarks, primarily targeting the $T$ quark decays to a $W$ boson and a $b$-quark. The search is based on $36.1$ fb$^{-1}$ of $pp$ collisions at $\sqrt{s}$ = 13 TeV recorded in 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. Data are analysed in the lepton-plus-jets final state, including at least one $b$-tagged jet and a large-radius jet identified as originating from the hadronic decay of a high-momentum $W$ boson. No significant deviation from the Standard Model expectation is observed in the reconstructed $T$ mass distribution. The observed 95\% confidence level lower limit on the $T$ mass are 1350 GeV assuming 100\% branching ratio to $Wb$. In the SU(2) singlet scenario, the lower mass limit is 1170 GeV. This search is also sensitive to a heavy vector-like $B$ quark decaying to $Wt$ and other final states. The results are thus reinterpreted to provide a 95\% confidence level lower limit on the $B$ quark mass at 1250 GeV assuming 100\% branching ratio to $Wt$; in the SU(2) singlet scenario, the limit is 1080 GeV. Mass limits on both $T$ and $B$ production are also set as a function of the decay branching ratios. The 100\% branching ratio limits are found to be applicable to heavy vector-like $Y$ and $X$ production that decay to $Wb$ and $Wt$, respectively.

7 data tables

The leptonic VLQ candidate mass distributions in the signal region after the maximum likelihood fit in the signal region and control region.

Expected and observed upper limits at the 95% CL on the TT cross section as a function of T quark mass under the assumption of BR(T->Wb)=1.

Expected and observed upper limits at the 95% CL on the TT cross section as a function of T quark mass for an SU(2) singlet T.

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Determination of the strong coupling constant $\alpha_s$ from transverse energy-energy correlations in multijet events at $\sqrt{s} = 8$ TeV using the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1609253 DOI 10.17182/hepdata.77269

Measurements of transverse energy-energy correlations and their associated asymmetries in multi-jet events using the ATLAS detector at the LHC are presented. The data used correspond to $\sqrt{s} = 8$ TeV proton-proton collisions with an integrated luminosity of 20.2 fb$^{-1}$. The results are presented in bins of the scalar sum of the transverse momenta of the two leading jets, unfolded to the particle level and compared to the predictions from Monte Carlo simulations. A comparison with next-to-leading-order perturbative QCD is also performed, showing excellent agreement within the uncertainties. From this comparison, the value of the strong coupling constant is extracted for different energy regimes, thus testing the running of $\alpha_s(\mu)$ predicted in QCD up to scales over 1 TeV. A global fit to the transverse energy-energy correlation distributions yields $\alpha_s(m_Z) = 0.1162 \pm 0.0011 \mbox{ (exp.)}^{+0.0084}_{-0.0070} \mbox{ (theo.)}$, while a global fit to the asymmetry distributions yields a value of $\alpha_s(m_Z) = 0.1196 \pm 0.0013 \mbox{ (exp.)}^{+0.0075}_{-0.0045} \mbox{ (theo.)}$.

16 data tables

TEEC function for 800 GeV < HT2 < 850 GeV

ATEEC function for 800 GeV < HT2 < 850 GeV

TEEC function for 850 GeV < HT2 < 900 GeV

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Search for Dark Matter Produced in Association with a Higgs Boson Decaying to $b\bar b$ using 36 fb$^{-1}$ of $pp$ collisions at $\sqrt s=13$ TeV with the ATLAS Detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1608773 DOI 10.17182/hepdata.77773

Several extensions of the Standard Model predict associated production of dark-matter particles with a Higgs boson. Such processes are searched for in final states with missing transverse momentum and a Higgs boson decaying to a $b\bar b$ pair with the ATLAS detector using 36.1 fb$^{-1}$ of $pp$ collisions at a center-of-mass energy of 13 TeV at the LHC. The observed data are in agreement with the Standard Model predictions and limits are placed on the associated production of dark-matter particles and a Higgs boson.

8 data tables

Distributions of the invariant mass of the Higgs boson candidates mh=m_jj with two b-tags in the SR for the first MET category that is used as input to the fit.

Distributions of the invariant mass of the Higgs boson candidates mh=m_jj with two b-tags in the SR for the second MET category that is used as input to the fit.

Distributions of the invariant mass of the Higgs boson candidates mh=m_jj with two b-tags in the SR for the third MET category that is used as input to the fit.

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Search for a new heavy gauge boson resonance decaying into a lepton and missing transverse momentum in 36 fb$^{-1}$ of $pp$ collisions at $\sqrt{s} =$ 13 TeV with the ATLAS experiment

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1605396 DOI 10.17182/hepdata.77273

The results of a search for new heavy $W^\prime$ bosons decaying to an electron or muon and a neutrino using proton-proton collision data at a centre-of-mass energy of $\sqrt{s} = 13$ TeV are presented. The dataset was collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider and corresponds to an integrated luminosity of 36.1 fb$^{-1}$. As no excess of events above the Standard Model prediction is observed, the results are used to set upper limits on the $W^\prime$ boson cross-section times branching ratio to an electron or muon and a neutrino as a function of the $W^\prime$ mass. Assuming a $W^\prime$ boson with the same couplings as the Standard Model $W$ boson, $W^\prime$ masses below 5.1 TeV are excluded at the 95% confidence level.

6 data tables

Transverse mass distribution for events satisfying all selection criteria in the electron channel.

Transverse mass distribution for events satisfying all selection criteria in the muon channel.

Upper limits at the 95% CL on the cross section for SSM W' production and decay to the electron+neutrino channel as a function of the W' pole mass.

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Version 2
Search for direct top squark pair production in events with a Higgs or $Z$ boson, 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 1604889 DOI 10.17182/hepdata.77997

A search for direct top squark pair production resulting in events with either a same-flavour opposite-sign dilepton pair with invariant mass compatible with a $Z$ boson or a pair of jets compatible with a Standard Model (SM) Higgs boson ($h$) is presented. Requirements on additional leptons, jets, jets identified as originating from $b$-quarks, and missing transverse momentum are imposed to target the other decay products of the top squark pair. The analysis is performed using proton-proton collision data at $\sqrt{s}=13$ TeV collected with the ATLAS detector at the LHC in 2015--2016, corresponding to an integrated luminosity of 36.1 fb$^{-1}$. No excess is observed in the data with respect to the SM predictions. The results are interpreted in two sets of models. In the first set, direct production of pairs of lighter top squarks ($\tilde{t}_1$) with long decay chains involving $Z$ or Higgs bosons is considered. The second set includes direct pair production of the heavier top squark pairs ($\tilde{t}_2$) decaying via $\tilde{t}_2 \rightarrow Z \tilde{t}_1 $ or $\tilde{t}_2 \rightarrow h \tilde{t}_1$. The results exclude at 95\% confidence level $\tilde{t}_2$ and $\tilde{t}_1$ masses up to about 800 GeV, extending the exclusion region of supersymmetric parameter space covered by previous LHC searches.

57 data tables

Number of signal events selected at different stages for some scenarios in the $\tilde{t}_2 \rightarrow h\tilde{t}_1$ with $\tilde{t}_1\to t\tilde{\chi}^0_1$ model.

Number of signal events selected at different stages for some scenarios in the $\tilde{t}_2 \rightarrow Z\tilde{t}_1$ with $\tilde{t}_1\to t\tilde{\chi}^0_1$ model.

Distribution of $m_{bb}$ for events passing all the signal selection requirements, except that on $m_{bb}$, for SR$^{1\ell 4b}_A$ after the background fit described in Section 5. The contributions from all SM backgrounds are shown; the bands represent the total uncertainty. The last bin in each figure contains the overflow.

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Measurement of $WW/WZ \to \ell \nu q q^{\prime}$ production with the hadronically decaying boson reconstructed as one or two jets in $pp$ collisions at $\sqrt{s}=8$ TeV with ATLAS, and constraints on anomalous gauge couplings

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2017.
Inspire Record 1602949 DOI 10.17182/hepdata.78399

This paper presents a study of the production of $WW$ or $WZ$ boson pairs, with one $W$ boson decaying to $e\nu$ or $\mu\nu$ and one $W$ or $Z$ boson decaying hadronically. The analysis uses 20.2 fb$^{-1}$ of $\sqrt{s}=8$ TeV $pp$ collision data, collected by the ATLAS detector at the Large Hadron Collider. Cross-sections for $WW/WZ$ production are measured in high-$p_{T}$ fiducial regions defined close to the experimental event selection. The cross-section is measured for the case where the hadronically decaying boson is reconstructed as two resolved jets, and the case where it is reconstructed as a single jet. The transverse momentum distribution of the hadronically decaying boson is used to search for new physics. Observations are consistent with the Standard Model predictions, and $95\%$ confidence intervals are calculated for parameters describing anomalous triple gauge-boson couplings.

7 data tables

Measured fiducial cross section in the WV->lvjj and WV->lvJ channels. Refer to the paper for details of applied event selection.

Correction factors D for WV->lvjj and WV->lvJ channels. D = fWW * CWW + (1-fWW) * CWZ. fWW is the predicted ratio of the WW fiducial cross section to the WW+WZ fiducial cross section: fWW = SIG_theo_WW * AWW / (SIG_theo_WW*AWW + SIG_theo_WZ*AWZ).

The expected and observed 95% confidence intervals for the anomalous coupling parameters defined in the EFT frame work. WV->lvjj cha