Search for dark matter produced in association with bottom or top quarks in $\sqrt{s}$ = 13 TeV pp collisions with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Eur.Phys.J.C 78 (2018) 18, 2018.
Inspire Record 1633591 DOI 10.17182/hepdata.80080

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and missing transverse momentum are considered. The analysis uses 36.1 $fb^{-1}$ of proton-proton collision data recorded by the ATLAS experiment at $\sqrt{s}$ = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are interpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour-neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross-section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour-charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements.

63 data tables

- - - - - - - - Overview of HEPData Record - - - - - - - - <br/><br/> <b>Systematic uncertainties:</b> <a href="80080?version=1&table=Table2">table</a><br/><br/> <b>Fit results:</b> <a href="80080?version=1&table=Table3">SRb1 and SRb2</a> <a href="80080?version=1&table=Table4">SRt1, SRt2 and SRt3</a><br/><br/> <b>Upper limits:</b> <a href="80080?version=1&table=Table5">table</a><br/><br/> <b>SR distributions:</b> <ul> <li><a href="80080?version=1&table=Table6">SRb1: $E_{\mathrm T}^{\mathrm{miss}}$</a> <li><a href="80080?version=1&table=Table7">SRb2: $\cos{\theta}^*_{bb}$</a> <li><a href="80080?version=1&table=Table8">SRt1: $m_{\mathrm T}^{\mathrm{b,min}}$</a> <li><a href="80080?version=1&table=Table9">SRt2: $E_{\mathrm T}^{\mathrm{miss,sig}}$</a> <li><a href="80080?version=1&table=Table10">SRt3: $\xi^{+}_{\ell\ell}$</a> <li><a href="80080?version=1&table=Table34">SRb1: jet $p_{T}$</a> <li><a href="80080?version=1&table=Table35">SRb2: $H_{\mathrm T}^{ratio}$</a> <li><a href="80080?version=1&table=Table36">SRt1: $\Delta R_{bb}$</a> <li><a href="80080?version=1&table=Table37">SRt2: $M_{\mathrm T}^{b,min}$</a> <li><a href="80080?version=1&table=Table38">SRt3: $\Delta \phi_{boost}$</a> </ul> <b>Exclusion limits:</b> <ul> <li>Scalar SRb2 <a href="80080?version=1&table=Table11">expected</a> <a href="80080?version=1&table=Table12">observed</a> <li>Scalar SRt1/SRt2 <a href="80080?version=1&table=Table13">expected</a> <a href="80080?version=1&table=Table14">observed</a> <li>Scalar SRt3 <a href="80080?version=1&table=Table15">expected</a> <a href="80080?version=1&table=Table16">observed</a> <li>Pseudo-scalar SRb2 <a href="80080?version=1&table=Table17">expected</a> <a href="80080?version=1&table=Table18">observed</a> <li>Pseudo-scalar SRt1/SRt2 <a href="80080?version=1&table=Table19">expected</a> <a href="80080?version=1&table=Table20">observed</a> <li>Pseudo-scalar SRt3 <a href="80080?version=1&table=Table21">expected</a> <a href="80080?version=1&table=Table22">observed</a> <li>Scalar, SRt1/SRt2 vs DM mass <a href="80080?version=1&table=Table23">expected</a> <a href="80080?version=1&table=Table24">observed</a> <li>Scalar, SRt3 vs DM mass <a href="80080?version=1&table=Table25">expected</a> <a href="80080?version=1&table=Table26">observed</a> <li>Pseudo-scalar, SRt1/SRt2 vs DM mass <a href="80080?version=1&table=Table27">expected</a> <a href="80080?version=1&table=Table28">observed</a> <li>Pseudo-scalar, SRt3 vs DM mass <a href="80080?version=1&table=Table29">expected</a> <a href="80080?version=1&table=Table30">observed</a> <li>Colour-charged scalar mediators ($b-$FDM) <a href="80080?version=1&table=Table32">expected</a> <a href="80080?version=1&table=Table33">observed</a> </ul> <b>Direct detection plot:</b> <a href="80080?version=1&table=Table31">table</a><br/><br/> <b>Acceptances:</b> <ul> <li><a href="80080?version=1&table=Table39">SRb1</a> <li><a href="80080?version=1&table=Table41">SRb2 scalar</a> <li><a href="80080?version=1&table=Table44">SRb2 pseudo-scalar</a> <li><a href="80080?version=1&table=Table45">SRt2 scalar</a> <li><a href="80080?version=1&table=Table46">SRt1 scalar</a> <li><a href="80080?version=1&table=Table49">SRt2 pseudo-scalar</a> <li><a href="80080?version=1&table=Table50">SRt1 pseudo-scalar</a> <li><a href="80080?version=1&table=Table53">SRt3 scalar</a> <li><a href="80080?version=1&table=Table55">SRt3 pseudo-scalar</a> </ul> <b>Efficiencies:</b> <ul> <li><a href="80080?version=1&table=Table40">SRb1</a> <li><a href="80080?version=1&table=Table42">SRb2 scalar</a> <li><a href="80080?version=1&table=Table43">SRb2 pseudo-scalar</a> <li><a href="80080?version=1&table=Table47">SRt2 scalar</a> <li><a href="80080?version=1&table=Table48">SRt1 scalar</a> <li><a href="80080?version=1&table=Table51">SRt2 pseudo-scalar</a> <li><a href="80080?version=1&table=Table52">SRt1 pseudo-scalar</a> <li><a href="80080?version=1&table=Table54">SRt3 scalar</a> <li><a href="80080?version=1&table=Table56">SRt3 pseudo-scalar</a> </ul> <b>Cutflows:</b> <ul> <li><a href="80080?version=1&table=Table57">SRb1</a> <li><a href="80080?version=1&table=Table58">SRb2</a> <li><a href="80080?version=1&table=Table59">SRt1 scalar</a> <li><a href="80080?version=1&table=Table60">SRt2 scalar</a> <li><a href="80080?version=1&table=Table61">SRt1 pseudo-scalar</a> <li><a href="80080?version=1&table=Table62">SRt2 pseudo-scalar</a> <li><a href="80080?version=1&table=Table63">SRt3</a> </ul> <b>Truth Code snippets</b> are available under "Resources" (purple button on the left)

Summary of the main systematic uncertainties and their impact on the total SM background prediction in each of the signal regions studied. A range is shown for the four bins composing SRb2 . The total systematic uncertainty can be different from the sum in quadrature of individual sources due to the correlations between them resulting from the fit to the data. The quoted theoretical uncertainties include modelling and cross-section uncertainties.

Fit results in SRb1 and SRb2 for an integrated luminosity of $36.1 fb^{-1}$. The background normalisation parameters are obtained from the background-only fit in the CRs and are applied to the SRs. Small backgrounds are indicated as Others. The dominant component of these smaller background sources in SRb1 is di-boson processes. Benchmark signal models yields are given for each SR. The uncertainties on the yields include all systematic uncertainties.

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Search for doubly charged Higgs boson production in multi-lepton final states with the ATLAS detector using proton-proton collisions at $\sqrt{s}$ = 13 TeV

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Eur.Phys.J.C 78 (2018) 199, 2018.
Inspire Record 1632760 DOI 10.17182/hepdata.80462

A search for doubly charged Higgs bosons with pairs of prompt, isolated, highly energetic leptons with the same electric charge is presented. The search uses a proton-proton collision data sample at a centre-of-mass energy of 13 TeV corresponding to 36.1 $\mathrm{fb}^{-1}$ of integrated luminosity recorded in 2015 and 2016 by the ATLAS detector at the LHC. This analysis focuses on the decays $H^{\pm\pm}\rightarrow e^{\pm}e^{\pm}$, $H^{\pm\pm}\rightarrow e^{\pm}\mu^{\pm}$ and $H^{\pm\pm}\rightarrow \mu^{\pm}\mu^{\pm}$, fitting the dilepton mass spectra in several exclusive signal regions. No significant evidence of a signal is observed and corresponding limits on the production cross-section are derived at 95% confidence level. The observed lower limit on the mass of a doubly charged Higgs boson only coupling to left-handed leptons ($e$,$\mu$) varies from 770 GeV to 870 GeV (850 GeV expected) for $B(H^{\pm\pm}\rightarrow \ell^{\pm}\ell^{\pm})$ = 100% and both the expected and observed mass limits are above 450 GeV for $B(H^{\pm\pm}\rightarrow \ell^{\pm}\ell^{\pm})$ = 10% and any combination of partial branching ratios.

32 data tables

Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 100\%$, $B(e \mu ) = 0\%$, and $B( \mu \mu ) = 0\%$.

Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 0\%$, $B(e \mu ) = 0\%$, and $B( \mu \mu ) = 100\%$.

Observed and expected upper limit on the cross-section for $pp \to H^{++}H^{--}$ for a combination of partial branching ratios of $B(ee) = 0\%$, $B(e \mu ) = 100\%$, and $B( \mu \mu ) = 0\%$.

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Search for heavy resonances decaying into $WW$ in the $e\nu\mu\nu$ 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.
Eur.Phys.J.C 78 (2018) 24, 2018.
Inspire Record 1628411 DOI 10.17182/hepdata.79407

A search for neutral heavy resonances is performed in the $WW\to e\nu\mu\nu$ decay channel using $pp$ collision data corresponding to an integrated luminosity of 36.1 fb$^{-1}$, collected at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. No evidence of such heavy resonances is found. In the search for production via the quark--antiquark annihilation or gluon--gluon fusion process, upper limits on $\sigma_X \times B(X \to WW)$ as a function of the resonance mass are obtained in the mass range between 200 GeV and up to 5 TeV for various benchmark models: a Higgs-like scalar in different width scenarios, a two-Higgs-doublet model, a heavy vector triplet model, and a warped extra dimensions model. In the vector-boson fusion process, constraints are also obtained on these resonances, as well as on a Higgs boson in the Georgi--Machacek model and a heavy tensor particle coupling only to gauge bosons.

32 data tables

Figure 1, left, subfigure a, Acceptance times efficiency as a function of signal mass for the ggF or qqA production. The "0" efficiency mass point means there's no such signal sample for the corresponding model.

Figure 1, right, subfigure b, Acceptance times efficiency as a function of signal mass for the VBF production. The "0" efficiency mass point means there's no such signal sample for the corresponding model.

Figure 2, left, subfigure a, Transverse mass distribution in the ggF top-quark control regions. For NWA signals, the "0" value means lack of statistics.

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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.
JHEP 01 (2018) 055, 2018.
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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Measurement of $W^{\pm}$ and $Z$-boson production cross sections in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abdallah, Jalal ; et al.
Phys.Lett.B 759 (2016) 601-621, 2016.
Inspire Record 1436497 DOI 10.17182/hepdata.73611

Measurements of the $W^{\pm} \rightarrow \ell^{\pm} \nu$ and $Z \rightarrow \ell^+ \ell^-$ production cross sections (where $\ell^{\pm}=e^{\pm},\mu^{\pm}$) in proton-proton collisions at $\sqrt{s}=13$ TeV are presented using data recorded by the ATLAS experiment at the Large Hadron Collider, corresponding to a total integrated luminosity of 81 pb$^{-1}$ The total inclusive $W^{\pm}$-boson production cross sections times the single-lepton-flavour branching ratios are $\sigma_{W^+}^{tot}= 11.83 \pm 0.02 (stat) \pm 0.32 (sys) \pm 0.25 (lumi)$ nb and $\sigma_{W^-}^{tot} = 8.79 \pm 0.02 (stat) \pm 0.24 (sys) \pm 0.18 (lumi)$ nb for $W^+$ and $W^-$, respectively. The total inclusive $Z$-boson production cross section times leptonic branching ratio, within the invariant mass window $66 < m_{\ell\ell} < 116$ GeV, is $\sigma_{Z}^{tot} = 1.981 \pm 0.007 (stat) \pm 0.038 (sys) \pm 0.042 (lumi)$ nb. The $W^+$, $W^-$, and $Z$-boson production cross sections and cross-section ratios within a fiducial region defined by the detector acceptance are also measured. The cross-section ratios benefit from significant cancellation of experimental uncertainties, resulting in $\sigma_{W^+}^{fid}/\sigma_{W^-}^{fid} = 1.295 \pm 0.003 (stat) \pm 0.010 (sys)$ and $\sigma_{W^{\pm}}^{fid}/\sigma_{Z}^{fid} = 10.31 \pm 0.04 (stat) \pm 0.20 (sys)$. Theoretical predictions, based on calculations accurate to next-to-next-to-leading order for quantum chromodynamics and to next-to-leading order for electroweak processes and which employ different parton distribution function sets, are compared to these measurements.

24 data tables

Measured fiducial cross section times leptonic branching ratio for W+ production in the W+ -> e+ nu final state.

Measured fiducial cross section times leptonic branching ratio for W- production in the W- -> e- nubar final state.

Measured fiducial cross section times leptonic branching ratio for Z/gamma* production in the Z/gamma* -> e+e- final state.

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