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Constraints on anomalous HVV couplings from the production of Higgs bosons decaying to $\tau$ lepton pairs

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev., 2019.
Inspire Record 1725474 DOI 10.17182/hepdata.87255

A study is presented of anomalous HVV interactions of the Higgs boson, including its $CP$ properties. The study uses Higgs boson candidates produced mainly in vector boson fusion and gluon fusion that subsequently decay to a pair of $\tau$ leptons. The data were recorded by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 35.9 fb$^{-1}$. A matrix element technique is employed for the analysis of anomalous interactions. The results are combined with those from the H$\to 4\ell$ decay channel presented earlier, yielding the most stringent constraints on anomalous Higgs boson couplings to electroweak vector bosons expressed as effective cross-section fractions and phases: the $CP$-violating parameter $f_{a3}\cos(\phi_{a3})=(0.00\pm0.27)\times10^{-3}$ and the $CP$-conserving parameters $f_{a2}\cos(\phi_{a2})=(0.08^{+1.04}_{-0.21})\times10^{-3}$, $f_{\Lambda1}\cos(\phi_{\Lambda1})=(0.00^{+0.53}_{-0.09})\times10^{-3}$, and $f_{\Lambda1}^{\mathrm{Z}\gamma}\cos(\phi_{\Lambda1}^{\mathrm{Z}\gamma})=(0.0^{+1.1}_{-1.3})\times10^{-3}$. The current data set does not allow for precise constraints on $CP$ properties in the gluon fusion process. The results are consistent with standard model expectations.

4 data tables

Observed and expected likelihood scans of $f_{\Lambda1}\cos\phi_{\Lambda1}$. See Section 4 of the paper for more details.

Observed and expected likelihood scans of $f_{\Lambda1}^{Z\gamma}\cos\phi_{\Lambda1}^{Z\gamma}$. See Section 4 of the paper for more details.

Observed and expected likelihood scans of $f_{a2}\cos\phi_{a2}$. See Section 4 of the paper for more details.

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Search for high-mass dilepton resonances using 139 fb$^{-1}$ of $pp$ collision data collected at $\sqrt{s}=$13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
No Journal Information, 2019.
Inspire Record 1725190 DOI 10.17182/hepdata.88425

A search for high-mass dielectron and dimuon resonances in the mass range of 250 GeV to 6 TeV is presented. The data were recorded by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=$13 TeV during Run 2 of the Large Hadron Collider and correspond to an integrated luminosity of 139 fb$^{-1}$. A functional form is fitted to the dilepton invariant-mass distribution to model the contribution from background processes, and a generic signal shape is used to determine the significance of observed deviations from this background estimate. No significant deviation is observed and upper limits are placed at the 95% confidence level on the fiducial cross-section times branching ratio for various resonance width hypotheses. The derived limits are shown to be applicable to spin-0, spin-1 and spin-2 signal hypotheses. For a set of benchmark models, the limits are converted into lower limits on the resonance mass and reach 4.5 TeV for the E6-motivated $Z^\prime_\psi$ boson. Also presented are limits on Heavy Vector Triplet model couplings.

24 data tables

Observed 95% exclusion contours in the HVT parameter space $\{g_h,g_f\}$ with $g_f\equiv g_l=g_q$ for a resonance mass of 3 TeV for the dilepton channel. The area outside the curves is excluded.

Observed 95% exclusion contours in the HVT parameter space $\{g_q,g_l\}$ with $g_h$ set to zero for a resonance mass of 3 TeV for the dilepton channel. The area outside the curves is excluded.

Expected 95% exclusion contours in the HVT parameter space $\{g_h,g_f\}$ with $g_f\equiv g_l=g_q$ for a resonance mass of 3 TeV for the dilepton channel. The area outside the curves is excluded.

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Measurement of the four-lepton invariant mass spectrum in 13 TeV proton-proton collisions with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2019.
Inspire Record 1720442 DOI 10.17182/hepdata.84818

A measurement of the four-lepton invariant mass spectrum is made with the ATLAS detector, using an integrated luminosity of 36.1 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV delivered by the Large Hadron Collider. The differential cross-section is measured for events containing two same-flavour opposite-sign lepton pairs. It exhibits a rich structure, with different mass regions dominated in the Standard Model by single $Z$ boson production, Higgs boson production, and $Z$ boson pair production, and non-negligible interference effects at high invariant masses. The measurement is compared with state-of-the-art Standard Model calculations, which are found to be consistent with the data. These calculations are used to interpret the data in terms of $gg\rightarrow ZZ \rightarrow 4\ell$ and $Z \rightarrow 4\ell$ subprocesses, and to place constraints on a possible contribution from physics beyond the Standard Model.

29 data tables

Measured and expected differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$

Measured and expected differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 0$< p_{T}^{4l} <$20 GeV

Measured and expected differential cross-section $\text{d}\sigma / \text{d} m_{4l}$ as a function of $m_{4l}$ in bin of 20$< p_{T}^{4l} <$50 GeV

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Pseudorapidity distributions of charged hadrons in xenon-xenon collisions at $\sqrt{s_\mathrm{NN}} =$ 5.44 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2019.
Inspire Record 1719334 DOI 10.17182/hepdata.88285

Measurements of the pseudorapidity distributions of charged hadrons produced in xenon-xenon collisions at a nucleon-nucleon centre-of-mass energy of $\sqrt{s_\mathrm{NN}} =$ 5.44 TeV are presented. The measurements are based on data collected by the CMS experiment at the LHC. The yield of primary charged hadrons produced in xenon-xenon collisions in the pseudorapidity range $|\eta| < $ 3.2 is determined using the silicon pixel detector in the CMS tracking system. For the 5% most central collisions, the charged-hadron pseudorapidity density in the midrapidity region $|\eta| <$ 0.5 is found to be 1187 $\pm$ 36 (syst), with a negligible statistical uncertainty. The rapidity distribution of charged hadrons is also presented in the range $|y| <$ 3.2 and is found to be independent of rapidity around $y =$ 0. Comparisons of charged-hadron multiplicities between xenon-xenon and lead-lead collisions at similar collision energies show that particle production at midrapidity is strongly dependent on the collision geometry in addition to the system size and collision energy.

7 data tables

Averaged and symmetrised charged-hadron pseudorapidity density distributions in XeXe collisions at $\sqrt{s_{NN}} = 5.44$ TeV, for events in the 0--80\%, 0--5\%, and 50--55\% centrality intervals. The total uncertainty is dominated by the systematic uncertainty, and statistical uncertainties are negligible.

Averaged and symmetrised charged-hadron rapidity density distributions in XeXe collisions at $\sqrt{s_{NN}} = 5.44$ TeV, for events in the 0--80\% centrality interval. The total uncertainty is dominated by the systematic uncertainty, and statistical uncertainties are negligible.

Charged-hadron pseudorapidity density in XeXe collisions at $\sqrt{s_{NN}} = 5.44$ TeV at midrapidity as a function of event centrality. The total uncertainty is dominated by the systematic uncertainty, and statistical uncertainties are negligible.

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Search for heavy charged long-lived particles in the ATLAS detector in 31.6 fb$^{-1}$ of proton-proton collision data at $\sqrt{s} = 13$ TeV

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2019.
Inspire Record 1718558 DOI 10.17182/hepdata.86565

A search for heavy charged long-lived particles is performed using a data sample of 31.6 fb$^{-1}$ of proton-proton collisions at $\sqrt{s} = 13$ TeV collected by the ATLAS experiment at the Large Hadron Collider. The search is based on observables related to ionization energy loss and time of flight, which are sensitive to the velocity of heavy charged particles traveling significantly slower than the speed of light. Multiple search strategies for a wide range of lifetimes, corresponding to path lengths of a few meters, are defined as model-independently as possible, by referencing several representative physics cases that yield long-lived particles within supersymmetric models, such as gluinos/squarks ($R$-hadrons), charginos and staus. No significant deviations from the expected Standard Model background are observed. Upper limits at 95% confidence level are provided on the production cross sections of long-lived $R$-hadrons as well as directly pair-produced staus and charginos. These results translate into lower limits on the masses of long-lived gluino, sbottom and stop $R$-hadrons, as well as staus and charginos of 2000 GeV, 1250 GeV, 1340 GeV, 430 GeV and 1090 GeV, respectively.

30 data tables

Lower mass requirement for signal regions.

Lower mass requirement for signal regions.

Expected and observed events in the 16 discovery regions along with the according control regions.

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Search for low-mass resonances decaying into two jets and produced in association with a photon using $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2019.
Inspire Record 1717700 DOI 10.17182/hepdata.85763

A search is performed for localised excesses in dijet mass distributions of low-dijet-mass events produced in association with a high transverse energy photon. The search uses up to 79.8 fb$^{-1}$ of LHC proton-proton collisions collected by the ATLAS experiment at a centre-of-mass energy of 13 TeV during 2015-2017. Two variants are presented: one which makes no jet flavour requirements and one which requires both jets to be tagged as $b$-jets. The observed mass distributions are consistent with multi-jet processes in the Standard Model. The data are used to set upper limits on the production cross-section for a benchmark $Z^\prime$ model and, separately, on generic Gaussian-shape contributions to the mass distributions, extending the current ATLAS constraints on dijet resonances to the mass range between 225 and 1100 GeV.

16 data tables

Dijet mass distribution for the flavour inclusive category. Data, estimated background and uncertainties are shown. Events are collected using the single-photon trigger and contain a $E_T^{\gamma} > 150$ GeV photon and two $p_T^{jet} > 25$ GeV jets.

Dijet mass distribution for the flavour inclusive category. Data, estimated background and uncertainties are shown. Events are collected using the combined trigger and contain a $E_T^{\gamma} > 95$ GeV photon and two $p_T^{jet} > 65$ GeV jets.

Dijet mass distribution for the b-tagged category. Data, estimated background and uncertainties are shown. Events are collected using the single-photon trigger and contain a $E_T^{\gamma} > 150$ GeV photon and two $p_T^{jet} > 25$ GeV jets.

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Measurement of ${\rm D^0}$, ${\rm D^+}$, ${\rm D^{*+}}$ and ${{\rm D^+_s}}$ production in pp collisions at $\mathbf{\sqrt{{\textit s}}~=~5.02~TeV}$ with ALICE

The ALICE collaboration Acharya, Shreyasi ; Adamova, Dagmar ; Adhya, Souvik Priyam ; et al.
No Journal Information, 2019.
Inspire Record 1716440 DOI 10.17182/hepdata.89326

The measurements of the production of prompt ${\rm D^0}$, ${\rm D^+}$, ${\rm D^{*+}}$, and ${{\rm D^+_s}}$ mesons in proton--proton (pp) collisions at $\sqrt{s}=5.02$ TeV with the ALICE detector at the Large Hadron Collider (LHC) are reported. D mesons were reconstructed at mid-rapidity ($|y|<0.5$) via their hadronic decay channels ${\rm D}^0 \to {\rm K}^-\pi^+$, ${\rm D}^+\to {\rm K}^-\pi^+\pi^+$, ${\rm D}^{*+} \to {\rm D}^0 \pi^+ \to {\rm K}^- \pi^+ \pi^+$, ${\rm D^{+}_{s}\to \phi\pi^+\to K^{+} K^{-} \pi^{+}}$, and their charge conjugates. The production cross sections were measured in the transverse momentum interval $0<p_{\rm T}<36~\mathrm{GeV}/c$ for ${\rm D^0}$, $1<p_{\rm T}<36~\mathrm{GeV}/c$ for ${\rm D^+}$ and ${\rm D^{*+}}$, and in $2<p_{\rm T}<24~\mathrm{GeV}/c$ for ${{\rm D^+_s}}$ mesons. Thanks to the higher integrated luminosity, an analysis in finer $p_{\rm T}$ bins with respect to the previous measurements at $\sqrt{s}=7$ TeV was performed, allowing for a more detailed description of the cross-section $p_{\rm T}$ shape. The measured $p_{\rm T}$-differential production cross sections are compared to the results at $\sqrt{s}=7$ TeV and to four different perturbative QCD calculations. Its rapidity dependence is also tested combining the ALICE and LHCb measurements in pp collisions at $\sqrt{s}=5.02$ TeV. This measurement will allow for a more accurate determination of the nuclear modification factor in p-Pb and Pb-Pb collisions performed at the same nucleon-nucleon centre-of-mass energy.

18 data tables

$p_{\rm T}$-differential cross section of prompt $\rm{D}^{0}$ mesons in pp collisions at $\sqrt{\rm{s_{NN}}}$=5.02 TeV in the rapidity interval $|y|$<0.5. Branching ratio of $\rm{D}^{0}\rightarrow K\pi$ : 0.0389.

$p_{\rm T}$-differential cross section of prompt $\rm{D^{+}}$ mesons in pp collisions at $\sqrt{\rm{s_{NN}}}$=5.02 TeV in the rapidity interval $|y|$<0.5. Branching ratio of $\rm D^{+-}\rightarrow K{\rm{\pi}}{\rm{\pi}}$ : 0.0898.

$p_{\rm T}$-differential cross section of prompt $\rm D^{*}$ mesons in pp collisions at $\sqrt{\rm{s_{NN}}}$=5.02 TeV in the rapidity interval $|y|$<0.5. Branching ratio of $\rm{D}^{*+}\rightarrow \rm{D}^{0}\pi\rightarrow K\pi\pi$ : 0.02633.

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Search for vector-like quarks in events with two oppositely charged leptons and jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J., 2018.
Inspire Record 1711260 DOI 10.17182/hepdata.85746

A search for the pair production of heavy vector-like partners T and B of the top and bottom quarks has been performed by the CMS experiment at the CERN LHC using proton-proton collisions at $\sqrt{s} =$ 13 TeV. The data sample was collected in 2016 and corresponds to an integrated luminosity of 35.9 fb$^{-1}$. Final states studied for $\mathrm{T\overline{T}}$ production include those where one of the T quarks decays via T$\to$tZ and the other via T$\to$bW, tZ, or tH, where H is a Higgs boson. For the $\mathrm{B\overline{B}}$ case, final states include those where one of the B quarks decays via B$\to$bZ and the other B$\to$tW, bZ, or bH. Events with two oppositely charged electrons or muons, consistent with coming from the decay of a Z boson, and jets are investigated. The number of observed events is consistent with standard model background estimations. Lower limits at 95% confidence level are placed on the masses of the T and B quarks for a range of branching fractions. Assuming 100% branching fractions for T$\to$tZ, and B$\to$bZ, T and B quark mass values below 1280 and 1130 GeV, respectively, are excluded.

19 data tables

The $S_{\rm T}$ distribution for group A before fitting.

The $S_{\rm T}$ distribution for group B before fitting.

The $S_{\rm T}$ distribution for group C before fitting.

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Properties of $g\rightarrow b\bar{b}$ at small opening angles in $pp$ collisions with the ATLAS detector at $\sqrt{s}=13$ TeV

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev. D99 (2019) 052004, 2019.
Inspire Record 1711114 DOI 10.17182/hepdata.85697

The fragmentation of high-energy gluons at small opening angles is largely unconstrained by present measurements. Gluon splitting to $b$-quark pairs is a unique probe into the properties of gluon fragmentation because identified $b$-tagged jets provide a proxy for the quark daughters of the initial gluon. In this study, key differential distributions related to the $g\rightarrow b\bar{b}$ process are measured using 33 fb$^{-1}$ of $\sqrt{s}=13$ TeV $pp$ collision data recorded by the ATLAS experiment at the LHC in 2016. Jets constructed from charged-particle tracks, clustered with the anti-$k_t$ jet algorithm with radius parameter $R = 0.2$, are used to probe angular scales below the $R=0.4$ jet radius. The observables are unfolded to particle level in order to facilitate direct comparisons with predictions from present and future simulations. Multiple significant differences are observed between the data and parton shower Monte Carlo predictions, providing input to improve these predictions of the main source of background events in analyses involving boosted Higgs bosons decaying into $b$-quarks.

4 data tables

Normalisaed differential cross section, $(1/\sigma_\text{fid})d\sigma_\text{fid}/d\Delta R(b,b)$, as a function of $\Delta R(b,b)$ - the angle in $\eta$ and $\phi$ between the two b-tagged jets.

Normalisaed differential cross section, $(1/\sigma_\text{fid})d\sigma_\text{fid}/d\Delta\theta_\text{gpp,gbb}/\pi$, the angle between production (gpp) and decay (gbb) planes ($\Delta\theta_\text{gpp,gbb}$).

Normalisaed differential cross section, $(1/\sigma_\text{fid})d\sigma_\text{fid}/dz(p_\text{T})$, as a function of $z(p_\text{T})=p_\text{T,2}/(p_\text{T,1}+p_\text{T,2})$.

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Search for heavy long-lived multi-charged particles in proton-proton collisions at $\sqrt{s}$ = 13 TeV using the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2018.
Inspire Record 1707957 DOI 10.17182/hepdata.85615

A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data with an integrated luminosity of 36.1 fb$^{-1}$ collected in 2015 and 2016 from proton-proton collisions at $\sqrt{s}$ = 13 TeV are examined. Particles producing anomalously high ionization, consistent with long-lived massive particles with electric charges from |q|=2e to |q|=7e, are searched for. No events are observed, and 95% confidence level cross-section upper limits are interpreted as lower mass limits for a Drell-Yan production model. Multi-charged particles with masses between 50 GeV and 980-1220 GeV are excluded.

3 data tables

The signal efficiency values versus mass values for different charges.

Expected cross-section upper limits on the production cross-section of MCPs as a function of simulated particle mass for different charges.

Observed cross-section upper limits on the production cross-section of MCPs as a function of simulated particle mass for different charges.


Charged-particle pseudorapidity density at mid-rapidity in p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 8.16 TeV

The ALICE collaboration Acharya, Shreyasi ; Torales - Acosta, Fernando ; Adamova, Dagmar ; et al.
Eur.Phys.J. C79 (2019) 307, 2019.
Inspire Record 1706753 DOI 10.17182/hepdata.89268

The pseudorapidity density of charged particles, $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$, in p-Pb collisions has been measured at a centre-of-mass energy per nucleon-nucleon pair of $\sqrt{s_{\rm{NN}}}$ = 8.16 TeV at mid-pseudorapidity for non-single-diffractive events. The results cover 3.6 units of pseudorapidity, $|\eta|<1.8$. The $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ value is $19.1\pm0.7$ at $|\eta|<0.5$. This quantity divided by $\langle N_\rm{part} \rangle/2$, is $4.73\pm0.20$, which is 9.5% higher than the corresponding value for p-Pb collisions at $\sqrt{s_{\rm{NN}}}$ = 5.02 TeV. Measurements are compared with models based on different mechanisms for particle production. All models agree within uncertainties with data in the Pb-going side, while HIJING overestimates, showing a symmetric behaviour, and EPOS underestimates the p-going side of the $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ distribution. Saturation-based models reproduce the distributions well for $\eta>-1.3$. The $\rm{d}\it{N}_\rm{ch}/\rm{d}\it{\eta}$ is also measured for different centrality estimators, based both on the charged-particle multiplicity and on the energy deposited in the Zero-Degree Calorimeters. A study of the implications of the large multiplicity fluctuations due to the small number of participants for systems like p-Pb in the centrality calculation for multiplicity-based estimators is discussed, demonstrating the advantages of determining the centrality with energy deposited near beam rapidity.

29 data tables

Pseudorapidity density of charged particles in p–Pb NSD collisions at a centre-of-mass energy of 8.16 TeV.

Values of average pseudorapidity density of charged particles in p–Pb NSD collisions as a function of the energy in the centre-of-mass.

Pseudorapidity density of charged particles in p–Pb NSD collisions at 8.16 TeV for 0-5% centrality class and CL1 estimator.

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Study of J/$\psi$ azimuthal anisotropy at forward rapidity in Pb-Pb collisions at $\sqrt{{\textit s}_{\rm NN}}$ = 5.02 TeV

The ALICE collaboration Acharya, Shreyasi ; Torales - Acosta, Fernando ; Adamova, Dagmar ; et al.
JHEP, 2018.
Inspire Record 1706006 DOI 10.17182/hepdata.88308

The second ($v_2$) and third ($v_3$) flow harmonic coefficients of J/$\psi$ mesons are measured at forward rapidity (2.5 $<$ $y$ $<$ 4.0) in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV with the ALICE detector at the LHC. Results are obtained with the scalar product method and reported as a function of transverse momentum, $p_{\rm{T}}$, for various collision centralities. A positive value of J/$\psi$ $v_3$ is observed with 3.7$\sigma$ significance. The measurements, compared to those of prompt D$^0$ mesons and charged particles at mid-rapidity, indicate an ordering with $v_{\rm n}$(J/$\psi$) $<v_{\rm n}$(D$^0$) $<v_{\rm n}$(h$^\pm$) (n = 2, 3) at low and intermediate $p_{\rm{T}}$ up to 6 GeV/$c$ and a convergence with $v_2$(J/$\psi$) $\approx v_2$(D$^0$) $\approx v_2$(h$^\pm$) at high $p_{\rm{T}}$ above 6-8 GeV/$c$. In semi-central collisions (5-40% and 10-50% centrality intervals) at intermediate $p_{\rm{T}}$ between 2 and 6 GeV/$c$, the ratio $v_3/v_2$ of J/$\psi$ mesons is found to be significantly lower (4.6$\sigma$) with respect to that of charged particles. In addition, the comparison to the prompt D$^0$-meson ratio in the same $p_{\rm{T}}$ interval suggests an ordering similar to that of the $v_2$ and $v_3$ coefficients. The J/$\psi$ $v_2$ coefficient is further studied using the Event Shape Engineering technique. The obtained results are found to be compatible with the expected variations of the eccentricity of the initial-state geometry.

12 data tables

The J/$\psi$ $v_2$ coefficient as a function of $p_{\rm T}$ in 0-10% centrality interval in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV.

The J/$\psi$ $v_2$ coefficient as a function of $p_{\rm T}$ in 10-30% centrality interval in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV.

The J/$\psi$ $v_2$ coefficient as a function of $p_{\rm T}$ in 30-50% centrality interval in Pb-Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV.

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Measurements of fiducial and differential cross-sections of $t\bar{t}$ production with additional heavy-flavour jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
No Journal Information, 2018.
Inspire Record 1705857 DOI 10.17182/hepdata.87098

This paper presents measurements of $t\bar{t}$ production in association with additional $b$-jets in $pp$ collisions at the LHC at a centre-of-mass energy of 13 TeV. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.1 fb$^{-1}$. Fiducial cross-section measurements are performed in the dilepton and lepton-plus-jets $t\bar{t}$ decay channels. Results are presented at particle level in the form of inclusive cross-sections of $t\bar{t}$ final states with three and four $b$-jets as well as differential cross-sections as a function of global event properties and properties of $b$-jet pairs. The measured inclusive fiducial cross-sections generally exceed the $t\bar{t}b\bar{b}$ predictions from various next-to-leading-order matrix element calculations matched to a parton shower but are compatible within the total uncertainties. The experimental uncertainties are smaller than the uncertainties in the predictions. Comparisons of state-of-the-art theoretical predictions with the differential measurements are shown and good agreement with data is found for most of them.

50 data tables

Relative differential cross section as a function of the b-jet multiplicity in emu channel

Relative differential cross section as a function of H_T in emu channel

Relative differential cross section as a function of H_T in emu channel