Measurement of the associated production of a Higgs boson decaying into $b$-quarks with a vector boson at high transverse momentum in $pp$ collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Phys.Lett.B 816 (2021) 136204, 2021.
Inspire Record 1810348 DOI 10.17182/hepdata.94801

The associated production of a Higgs boson with a $W$ or $Z$ boson decaying into leptons and where the Higgs boson decays to a $b\bar{b}$ pair is measured in the high vector-boson transverse momentum regime, above 250 GeV, with the ATLAS detector. The analysed data, corresponding to an integrated luminosity of 139 fb$^{-1}$, were collected in proton-proton collisions at the Large Hadron Collider between 2015 and 2018 at a centre-of-mass energy of $\sqrt{s} = 13$ TeV. The measured signal strength, defined as the ratio of the measured signal yield to that predicted by the Standard Model, is $0.72 ^{+0.39}_{-0.36}$ corresponding to an observed (expected) significance of 2.1 (2.7) standard deviations. Cross-sections of associated production of a Higgs boson decaying into $b$ quark pairs with a $W$ or $Z$ gauge boson, decaying into leptons, are measured in two exclusive transverse momentum regions, 250-400 GeV and above 400 GeV, and interpreted as constraints on anomalous couplings in the framework of a Standard Model effective field theory.

3 data tables

Observed correlations between the measured reduced stage-1.2 simplified template VH, V->leptons and H->bb cross sections, including both the statistical and systematic uncertainties.

Measured and predicted VH, V->leptons reduced stage-1.2 simplified template cross sections times the H->bb and V->leptons branching fractions with corresponding uncertainties. All possible Z decays into neutral and charged leptons are considered.

Linear combinations of Wilson coefficients corresponding to the principal component decomposition eigenvectors. The corresponding eigenvalues, representing in the gaussian approximation the inverse uncertainty square of the measured eigenvector, is also indicated.


Measurements of inclusive and differential cross-sections of combined $ t\overline{t}\gamma $ and $tW\gamma$ production in the e$\mu$ channel at 13 TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 09 (2020) 049, 2020.
Inspire Record 1806806 DOI 10.17182/hepdata.94915

Inclusive and differential cross-sections for the production of top quarks in association with a photon are measured with proton$-$proton collision data corresponding to an integrated luminosity of 139 fb$^{-1}$. The data were collected by the ATLAS detector at the LHC during Run 2 between 2015 and 2018 at a centre-of-mass energy of 13 TeV. The measurements are performed in a fiducial volume defined at parton level. Events with exactly one photon, one electron and one muon of opposite sign, and at least two jets, of which at least one is $b$-tagged, are selected. The fiducial cross-section is measured to be $39.6\,^{+2.7}_{-2.3}\,\textrm{fb}$. Differential cross-sections as functions of several observables are compared with state-of-the-art Monte Carlo simulations and next-to-leading-order theoretical calculations. These include cross-sections as functions of photon kinematic variables, angular variables related to the photon and the leptons, and angular separations between the two leptons in the event. All measurements are in agreement with the predictions from the Standard Model.

24 data tables

The measured fiducial cross-section in the electron-muon channel. The first uncertainty is the statistical uncertainty and the second one is the systematic uncertainty.

The absolute differential cross-section measured in the fiducial phase-space as a function of the photon pT in the electron-muon channel. The uncertainty is decomposed into four components which are the signal modelling uncertainty, the background modelling uncertainty, the experimental uncertainty, and the data statistical uncertainty.

The absolute differential cross-section measured in the fiducial phase-space as a function of the photon $|\eta|$ in the electron-muon channel. The uncertainty is decomposed into four components which are the signal modelling uncertainty, the background modelling uncertainty, the experimental uncertainty, and the data statistical uncertainty.

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Differential cross-section measurements for the electroweak production of dijets in association with a $Z$ boson in proton–proton collisions at ATLAS

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
Eur.Phys.J.C 81 (2021) 163, 2021.
Inspire Record 1803608 DOI 10.17182/hepdata.94218

Differential cross-section measurements are presented for the electroweak production of two jets in association with a $Z$ boson. These measurements are sensitive to the vector-boson fusion production mechanism and provide a fundamental test of the gauge structure of the Standard Model. The analysis is performed using proton-proton collision data collected by ATLAS at $\sqrt{s}$=13 TeV and with an integrated luminosity of 139 fb$^{-1}$. The differential cross-sections are measured in the $Z\rightarrow \ell^+\ell^-$ decay channel ($\ell=e,\mu$) as a function of four observables: the dijet invariant mass, the rapidity interval spanned by the two jets, the signed azimuthal angle between the two jets, and the transverse momentum of the dilepton pair. The data are corrected for the effects of detector inefficiency and resolution and are sufficiently precise to distinguish between different state-of-the-art theoretical predictions calculated using Powheg+Pythia8, Herwig7+Vbfnlo and Sherpa 2.2. The differential cross-sections are used to search for anomalous weak-boson self-interactions using a dimension-six effective field theory. The measurement of the signed azimuthal angle between the two jets is found to be particularly sensitive to the interference between the Standard Model and dimension-six scattering amplitudes and provides a direct test of charge-conjugation and parity invariance in the weak-boson self-interactions.

21 data tables

Differential cross-sections for EW $Zjj$ production as a function of $m_{jj}$ with breakdown of associated uncertainties. The statistical uncertainty is correlated across bins according to the statistical cross correlation matrix presented in Table 21.

Differential cross-sections for EW $Zjj$ production as a function of $|\Delta y_{jj}|$ with breakdown of associated uncertainties. The statistical uncertainty is correlated across bins according to the statistical cross correlation matrix presented in Table 21.

Differential cross-sections for EW $Zjj$ production as a function of $p_{\mathrm{T},\ell\ell}$ with breakdown of associated uncertainties. The statistical uncertainty is correlated across bins according to the statistical cross correlation matrix presented in Table 21.

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Measurements of the production cross-section for a $Z$ boson in association with $b$-jets in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 07 (2020) 044, 2020.
Inspire Record 1788444 DOI 10.17182/hepdata.94219

This paper presents a measurement of the production cross-section of a $Z$ boson in association with $b$-jets, in proton-proton collisions at $\sqrt{s} = 13$ TeV with the ATLAS experiment at the Large Hadron Collider using data corresponding to an integrated luminosity of 35.6 fb$^{-1}$. Inclusive and differential cross-sections are measured for events containing a $Z$ boson decaying into electrons or muons and produced in association with at least one or at least two $b$-jets with transverse momentum $p_\textrm{T}>$ 20 GeV and rapidity $|y| < 2.5$. Predictions from several Monte Carlo generators based on leading-order (LO) or next-to-leading-order (NLO) matrix elements interfaced with a parton-shower simulation and testing different flavour schemes for the choice of initial-state partons are compared with measured cross-sections. The 5-flavour number scheme predictions at NLO accuracy agree better with data than 4-flavour number scheme ones. The 4-flavour number scheme predictions underestimate data in events with at least one b-jet.

15 data tables

Measured fiducial cross sections for events with $Z(\rightarrow ll)\ge+1$ b-jets or with $Z(\rightarrow ll)\ge+2$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the Z boson $p_{\text{T}}$ in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

Differential fiducial cross section of the leading b-jet $p_{\text{T}}$ in events with $Z(\rightarrow ll)\ge+1$ b-jets. The statistical uncertainties and the individual components of systematic uncertainty are given in each bin. Statistical uncertainties are bin-to-bin uncorrelated.

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Version 2
Measurement of the $Z(\rightarrow\ell^+\ell^-)\gamma$ production cross-section in $pp$ collisions at $\sqrt{s} =13$ TeV with the ATLAS detector

The ATLAS collaboration Aad, Georges ; Abbott, Brad ; Abbott, Dale Charles ; et al.
JHEP 03 (2020) 054, 2020.
Inspire Record 1764342 DOI 10.17182/hepdata.89875

The production of a prompt photon in association with a $Z$ boson is studied in proton-proton collisions at a centre-of-mass energy $\sqrt{s} =$ 13 TeV. The analysis uses a data sample with an integrated luminosity of 139 fb$^{-1}$ collected by the ATLAS detector at the LHC from 2015 to 2018. The production cross-section for the process $pp \rightarrow \ell^+\ell^-\gamma+X$ ($\ell = e, \mu$) is measured within a fiducial phase-space region defined by kinematic requirements on the photon and the leptons, and by isolation requirements on the photon. An experimental precision of 2.9% is achieved for the fiducial cross-section. Differential cross-sections are measured as a function of each of six kinematic variables characterising the $\ell^+\ell^-\gamma$ system. The data are compared with theoretical predictions based on next-to-leading-order and next-to-next-to-leading-order perturbative QCD calculations. The impact of next-to-leading-order electroweak corrections is also considered.

7 data tables

The measured fiducial cross section. "Uncor" uncertainty includes all systematic uncertainties that are uncorrelated between electron and muon channels such as the uncertainty on the electron identification efficiency and the uncorrelated component of the background uncertainties. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production of 4.57 fb.

The measured fiducial cross section vs $E_{\mathrm{T}}^\gamma$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

The measured fiducial cross section vs $|\eta^\gamma|$. The central values are provided along with the statistical and systematic uncertainties together with the sign information. The statistical and "Uncor" uncertainty should be treated as uncorrelated bin-to-bin, while the rest are correlated between bins, and they are written as signed NP variations. The parton-to-particle correction factor $C_{theory}$ is the ratio of the cross-section predicted by Sherpa LO samples at particle level within the fiducial phase-space region defined in Table 4 to the predicted cross-section at parton level within the same fiducial region but with the smooth-cone isolation prescription defined above replacing the particle-level photon isolation criterion, and with Born-level leptons in place of dressed leptons. This correction should be applied on fixed order parton-level calculations. The systematic uncertainty is evaluated from a comparison with the correction factor obtained using events generated with SHERPA 2.2.2 at NLO. In the case that the calculations are valid for dressed leptons, a modified correction factor excluding the Born-to-dressed lepton correction should be applied instead. This correction only takes into account the particle-level isolation criteria, and is provided separately here. The Sherpa 2.2.8 NLO cross-sections given below include a small contribution from EW $Z\gamma jj$ production.

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Measurements of Higgs boson properties in the diphoton decay channel with 36 fb$^{-1}$ of $pp$ collision data at $\sqrt{s} = 13$ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Rev.D 98 (2018) 052005, 2018.
Inspire Record 1654582 DOI 10.17182/hepdata.83417

Properties of the Higgs boson are measured in the two-photon final state using 36.1 fb$^{-1}$ of proton-proton collision data recorded at $\sqrt{s} = 13$ TeV by the ATLAS experiment at the Large Hadron Collider. Cross-section measurements for the production of a Higgs boson through gluon-gluon fusion, vector-boson fusion, and in association with a vector bosonor a top-quark pair are reported. The signal strength, defined as the ratio of the observed to the expected signal yield, is measured for each of these production processes as well as inclusively. The global signal strength measurement of $0.99 \pm 0.14$ improves on the precision of the ATLAS measurement at $\sqrt{s} = 7$ and 8 TeV by a factor of two. Measurements of gluon-gluon fusion and vector-boson fusion productions yield signal strengths compatible with the Standard Model prediction. Measurements of simplified template cross sections, designed to quantify the different Higgs boson production processes in specific regions of phase space, are reported. The cross section for the production of the Higgs boson decaying to two isolated photons in a fiducial region closely matching the experimental selection of the photons is measured to be $55 \pm 10$ fb, which is in good agreement with the Standard Model prediction of $64 \pm 2$ fb. Furthermore, cross sections in fiducial regions enriched in Higgs boson production in vector-boson fusion or in association with large missing transverse momentum, leptons or top-quark pairs are reported. Differential and double-differential measurements are performed for several variables related to the diphoton kinematics as well as the kinematics and multiplicity of the jets produced in association with a Higgs boson. No significant deviations from a wide array of Standard Model predictions are observed.

39 data tables

Measured differential cross section with associated uncertainties as a function of PT(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

Measured differential cross section with associated uncertainties as a function of YRAP(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

Measured differential cross section with associated uncertainties as a function of PTTHRUST(2GAMMA). Each systematic uncertainty sources is fully uncorrelated with the other sources and fully correlated across bins, except for the background modelling systematics for which an uncorrelated treatment across bins is more appropriate.

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Measurement of the cross section for isolated-photon plus jet production in $pp$ collisions at $\sqrt s=13$ TeV using the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Phys.Lett.B 780 (2018) 578-602, 2018.
Inspire Record 1645627 DOI 10.17182/hepdata.78401

The dynamics of isolated-photon production in association with a jet in proton-proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb$^{-1}$. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti-$k_t$ algorithm with radius parameter $R=0.4$ and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon-jet invariant mass and the scattering angle in the photon-jet centre-of-mass system. Tree-level plus parton-shower predictions from SHERPA and PYTHIA as well as next-to-leading-order QCD predictions from JETPHOX and SHERPA are compared to the measurements.

5 data tables

Measured cross sections for isolated-photon plus jet production as a function of $E_{\rm T}^{\gamma}$.

Measured cross sections for isolated-photon plus jet production as a function of $p_{\rm T}^{\rm jet-lead}$.

Measured cross sections for isolated-photon plus jet production as a function of $\Delta\phi^{\rm \gamma-jet\ lead}$.

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Measurement of the $ t\overline{t}\gamma $ production cross section in proton-proton collisions at $ \sqrt{s}=8 $ TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
JHEP 11 (2017) 086, 2017.
Inspire Record 1604029 DOI 10.17182/hepdata.81946

The cross section of a top-quark pair produced in association with a photon is measured in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} = 8$ TeV with $20.2$ fb$^{-1}$ of data collected by the ATLAS detector at the Large Hadron Collider in 2012. The measurement is performed by selecting events that contain a photon with transverse momentum $p_\mathrm{T} > 15$ GeV, an isolated lepton with large transverse momentum, large missing transverse momentum, and at least four jets, where at least one is identified as originating from a $b$-quark. The production cross section is measured in a fiducial region close to the selection requirements. It is found to be $139 \pm 7 (\mathrm{stat.}) \pm 17 (\mathrm{syst.})$ fb, in good agreement with the theoretical prediction at next-to-leading order of $151 \pm 24$ fb. In addition, differential cross sections in the fiducial region are measured as a function of the transverse momentum and pseudorapidity of the photon.

3 data tables

The measured fiducial cross sections. The first uncertainty is the statistical uncertainty and the second is the systematic uncertainty

differential cross section as function of the photon pT. The first uncertainty is the statistical uncertainty and the second is the systematic uncertainty

differential cross section as function of the photon pseudorapidity. The first uncertainty is the statistical uncertainty and the second is the systematic uncertainty


Version 2
Fiducial, total and differential cross-section measurements of $t$-channel single top-quark production in $pp$ collisions at 8 TeV using data collected by the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Eur.Phys.J.C 77 (2017) 531, 2017.
Inspire Record 1512776 DOI 10.17182/hepdata.82544

Detailed measurements of $t$-channel single top-quark production are presented. They use 20.2 fb$^{-1}$ of data collected by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of 8 TeV at the LHC. Total, fiducial and differential cross-sections are measured for both top-quark and top-antiquark production. The fiducial cross-section is measured with a precision of 5.8 % (top quark) and 7.8 % (top antiquark), respectively. The total cross-sections are measured to be $\sigma_{\mathrm{tot}}(tq) = 56.7^{+4.3}_{-3.8}\;$pb for top-quark production and $\sigma_{\mathrm{tot}}(\bar{t}q) = 32.9^{+3.0}_{-2.7}\;$pb for top-antiquark production, in agreement with the Standard Model prediction. In addition, the ratio of top-quark to top-antiquark production cross-sections is determined to be $R_t=1.72 \pm 0.09$, with an improved relative precision of 4.9 % since several systematic uncertainties cancel in the ratio. The differential cross-sections as a function of the transverse momentum and rapidity of both the top quark and the top antiquark are measured at both the parton and particle levels. The transverse momentum and rapidity differential cross-sections of the accompanying jet from the $t$-channel scattering are measured at particle level. All measurements are compared to various Monte Carlo predictions as well as to fixed-order QCD calculations where available.

79 data tables

Predicted and observed event yields for the signal region (SR). The multijet background prediction is obtained from a binned maximum-likelihood fit to the $E_{\mathrm{T}}^{\mathrm{miss}}$ distribution. All the other predictions are derived using theoretical cross-sections, given for the backgrounds in Sect. 6 and for the signal in Sect. 1. The quoted uncertainties are in the predicted cross-sections or in the number of multijet events, in case of the multijet process.

Definition of the fiducial phase space.

The seven input variables to the NN ordered by their discriminating power. The jet that is not $b$-tagged is referred to as $\textit{untagged}~$jet.

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High-$E_{\rm T}$ isolated-photon plus jets production in $pp$ collisions at $\sqrt s=$ 8 TeV with the ATLAS detector

The ATLAS collaboration Aaboud, Morad ; Aad, Georges ; Abbott, Brad ; et al.
Nucl.Phys.B 918 (2017) 257-316, 2017.
Inspire Record 1499475 DOI 10.17182/hepdata.79948

The dynamics of isolated-photon plus one-, two- and three-jet production in $pp$ collisions at a centre-of-mass energy of 8 TeV are studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 20.2 fb$^{-1}$. Measurements of isolated-photon plus jets cross sections are presented as functions of the photon and jet transverse momenta. The cross sections as functions of the azimuthal angle between the photon and the jets, the azimuthal angle between the jets, the photon-jet invariant mass and the scattering angle in the photon-jet centre-of-mass system are presented. The pattern of QCD radiation around the photon and the leading jet is investigated by measuring jet production in an annular region centred on each object; enhancements are observed around the leading jet with respect to the photon in the directions towards the beams. The experimental measurements are compared to several different theoretical calculations, and overall a good description of the data is found.

35 data tables

Measured cross sections for isolated-photon plus 1jet production as a function of $E_{\rm T}^{\gamma}$.

Measured cross sections for isolated-photon plus 1jet production as a function of $p_{\rm T}^{\rm jet1}$.

Measured cross sections for isolated-photon plus 1jet production as a function of $m^{\gamma-\rm jet1}$.

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