Guy Steve Muanza

• PhD, Habilitation
• Staff Physicist in Experimental Particle Physics at Institut National de Physique Nucléaire et de Physique des Particules

We propose a novel method for an indirect measurement of the mass of final states produced through charged current processes at the LHC. This method is based upon the process integral charge asymmetry. First, the theoretical prediction of the integral charge asymmetry and its related uncertainties are studied through parton level cross sections cal...

A search for heavy pseudoscalar (A) and scalar (H) Higgs bosons decaying into a top quark pair (tt¯) has been performed with 20.3 fb−1 of proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider at a center-of-mass energy s=8 TeV. Interference effects between the signal process and standard model tt¯ production, w...

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 bb¯ 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 ob...

These proceedings provide an overview of the new results obtained with the ATLAS detector at the LHC, which were presented in the Quark Matter 2017 conference. These results were covered by twelve parallel talks, one flash talk and eleven posters. These proceedings group these results into five areas: initial state, jet quenching, quarkonium produc...

These proceedings provide an overview of the new results obtained with the ATLAS detector at the LHC, which were presented in the Quark Matter 2017 conference. These results were covered by twelve parallel talks, one flash talk and eleven posters. These proceedings group these results into five areas: initial state, jet quenching, quarkonium produc...

A measurement of b-hadron pair production is presented, based on a data set corresponding to an integrated luminosity of 11.4 fb−1 of proton-proton collisions recorded at \( \sqrt{s}=8 \) TeV with the ATLAS detector at the LHC. Events are selected in which a b-hadron is reconstructed in a decay channel containing J/ψ → μμ, and a second b-hadron is...

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 p...

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¯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 ob...

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 mom...

Ultra-peripheral heavy ion collisions provide a unique opportunity to study the parton distributions in the colliding nuclei via the measurement of photo-nuclear jet production. An analysis of jet production in ultra-peripheral Pb+Pb collisions at √sNN = 5.02 TeV performed using data collected with the ATLAS detector in 2015 is described. The data...

This paper presents single lepton and dilepton kinematic distributions measured in dileptonic \(t\bar{t}\) events produced in 20.2\(\hbox {fb}^{-1}\) of \(\sqrt{s}=8\) TeV pp collisions recorded by the ATLAS experiment at the LHC. Both absolute and normalised differential cross-sections are measured, using events with an opposite-charge \(e\mu \) p...

Measurements of differential cross-sections of top-quark pair production in fiducial phase-spaces are presented as a function of top-quark and \( t\overline{t} \) system kinematic observables in proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=13 \) TeV. The data set corresponds to an integrated luminosity of 3.2 fb−1, recorded in...

This article presents a search for flavour-changing neutral currents in the decay of a top quark into an up-type (q = c, u) quark and a Higgs boson, where the Higgs boson decays into two photons. The proton-proton collision data set analysed amounts to 36.1 fb−1 at √ s = 13 TeV collected by the ATLAS experiment at the LHC. Top quark pair events are...

This article presents searches for the Zγ decay of the Higgs boson and for narrow high-mass resonances decaying to Zγ, exploiting Z boson decays to pairs of electrons or muons. The data analysis uses 36.1 fb−1 of pp collisions at √ s = 13 recorded by the ATLAS detector at the CERN Large Hadron Collider. The data are found to be consistent with the...

Jet energy scale measurements and their systematic uncertainties are reported for jets measured with the ATLAS detector using proton-proton collision data with a center-of-mass energy of s=13 TeV, corresponding to an integrated luminosity of 3.2 fb−1 collected during 2015 at the LHC. Jets are reconstructed from energy deposits forming topological c...

With the increase in energy of the Large Hadron Collider to a centre-of-mass energy of 13 \(\text {TeV}\) for Run 2, events with dense environments, such as in the cores of high-energy jets, became a focus for new physics searches as well as measurements of the Standard Model. These environments are characterized by charged-particle separations of...

This article presents searches for the Zγ decay of the Higgs boson and for narrow high-mass resonances decaying to Zγ, exploiting Z boson decays to pairs of electrons or muons. The data analysis uses 36.1 fb⁻¹ of pp collisions at s=13 recorded by the ATLAS detector at the CERN Large Hadron Collider. The data are found to be consistent with the expe...

A search is presented for the pair production of heavy vector-like T 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 fina...

This article presents a search for flavour-changing neutral currents in the decay of a top quark into an up-type (q = c, u) quark and a Higgs boson, where the Higgs boson decays into two photons. The proton-proton collision data set analysed amounts to 36.1 fb−1 at \( \sqrt{s}=13 \) TeV collected by the ATLAS experiment at the LHC. Top quark pair e...

Inclusive and differential fiducial cross sections of Higgs boson production in proton-proton collisions are measured in the H → ZZ* → 4ℓ decay channel. The proton-proton collision data were produced at the Large Hadron Collider at a centre-of-mass energy of 13 TeV and recorded by the ATLAS detector in 2015 and 2016, corresponding to an integrated...

The cross-section for the production of two jets in association with a leptonically decaying Z boson (Zjj ) is measured in proton–proton collisions at a centre-of-mass energy of 13 TeV, using data recorded with the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 3.2 fb⁻¹. The electroweak Zjj cross-section i...

A search is conducted for new resonant and non-resonant high-mass phenomena in dielectron and dimuon final states. The search uses 36.1 fb−1 of proton-proton collision data, collected at \( \sqrt{s}=13 \) TeV by the ATLAS experiment at the LHC in 2015 and 2016. No significant deviation from the Standard Model prediction is observed. Upper limits at...

Dijet events are studied in the proton-proton collision data set recorded at s=13 TeV with the ATLAS detector at the Large Hadron Collider in 2015 and 2016, corresponding to integrated luminosities of 3.5 fb−1 and 33.5 fb−1 respectively. Invariant mass and angular distributions are compared to background predictions and no significant deviation is...

The rejection of forward jets originating from additional proton–proton interactions (pile-up) is crucial for a variety of physics analyses at the LHC, including Standard Model measurements and searches for physics beyond the Standard Model. The identification of such jets is challenging due to the lack of track and vertex information in the pseudo...

Inclusive jet production cross-sections are measured in proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV recorded by the ATLAS experiment at the Large Hadron Collider at CERN. The total integrated luminosity of the analysed data set amounts to 20.2 fb−1. Double-differential cross-sections are measured for jets defined by...

A search for new phenomena in final states characterized by high jet multiplicity, an isolated lepton (electron or muon) and either zero or at least three b-tagged jets is presented. The search uses 36.1 fb−1 of \( \sqrt{s}=13 \) TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider in 2015 and 2016. The do...

The rejection of forward jets originating from additional proton–proton interactions (pile-up) is crucial for a variety of physics analyses at the LHC, including Standard Model measurements and searches for physics beyond the Standard Model. The identification of such jets is challenging due to the lack of track and vertex information in the pseudo...

A search for strongly produced supersymmetric particles using signatures involving multiple energetic jets and either two isolated same-sign leptons (e or μ), or at least three isolated leptons, is presented. The analysis relies on the identification of b-jets and high missing transverse momentum to achieve good sensitivity. A data sample of proton...

This paper presents a study of \(WW\gamma \) and \(WZ\gamma \) triboson production using events from proton–proton collisions at a centre-of-mass energy of \(\sqrt{s} = \text{8}\,\text{TeV}\) recorded with the ATLAS detector at the LHC and corresponding to an integrated luminosity of 20.2 fb\(^{-1}\). The \(WW\gamma \) production cross-section is d...

The top-quark mass is measured in the all-hadronic top-antitop quark decay channel using proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV with the ATLAS detector at the CERN Large Hadron Collider. The data set used in the analysis corresponds to an integrated luminosity of 20.2 fb−1. The large multi-jet background is mode...

A search for heavy resonances decaying to a W or Z boson and a Higgs boson in the qq¯(′)bb¯ final state is described. The search uses 36.1 fb−1 of proton–proton collision data at 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 large...

Measurements of dijet pT correlations in Pb+Pb and pp collisions at a nucleon–nucleon centre-of-mass energy of sNN=2.76 TeV are presented. The measurements are performed with the ATLAS detector at the Large Hadron Collider using Pb+Pb and pp data samples corresponding to integrated luminosities of 0.14 nb−1 and 4.0 pb−1, respectively. Jets are reco...

Light-by-light scattering (γ γ → γ γ ) is a quantum-mechanical process that is forbidden in the classical theory of electrodynamics. This reaction is accessible at the Large Hadron Collider thanks to the large electromagnetic field strengths generated by ultra-relativistic colliding lead ions. Using 480 µb −1 of lead–lead collision data recorded at...

A search for the dimuon decay of the Higgs boson was performed using data corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector in pp collisions at s=13 TeV at the Large Hadron Collider. No significant excess is observed above the expected background. The observed (expected) upper limit on the cross section times...

A search for the dimuon decay of the Higgs boson was performed using data corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector in pp collisions at √s=13 TeV at the Large Hadron Collider. No significant excess is observed above the expected background. The observed (expected) upper limit on the cross section times...

A measurement of the splitting scales occuring in the kt jet-clustering algorithm is presented for final states containing a Z boson. The measurement is done using 20.2 fb−1 of proton-proton collision data collected at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV by the ATLAS experiment at the LHC in 2012. The measurement is based on chargedpart...

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 \(20.2~\text{ fb }^{-1}\) of \(\sqrt{s} =8~\text {TeV}\)pp collision data, collected by the ATLAS detector at the Large Hadron Collider. Cross-sections for WW / W...

The production of opposite-charge W-boson pairs in proton–proton collisions at s=13 TeV is measured using data corresponding to 3.16 fb−1 of integrated luminosity collected by the ATLAS detector at the CERN Large Hadron Collider in 2015. Candidate W-boson pairs are selected by identifying their leptonic decays into an electron, a muon and neutrinos...

ATLAS measurements of two-particle correlations are presented for √s=5.02 and 13 TeV pp collisions and for √sNN=5.02 TeV p+Pb collisions at the LHC. The correlation functions are measured as a function of relative azimuthal angle Δϕ, and pseudorapidity separation Δη, using charged particles detected within the pseudorapidity interval |η|<2.5. Azimu...

Inclusive isolated-photon production in pp collisions at a centre-of-mass energy of 13 TeV is studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 3.2 fb−1. The cross section is measured as a function of the photon transverse energy above 125 GeV in different regions of photon pseudorapidity. Next-to-leading-...

This paper describes the implementation and performance of a particle flow algorithm applied to 20.2 fb\(^{-1}\) of ATLAS data from 8 TeV proton–proton collisions in Run 1 of the LHC. The algorithm removes calorimeter energy deposits due to charged hadrons from consideration during jet reconstruction, instead using measurements of their momenta fro...

This paper describes the implementation and performance of a particle flow algorithm applied to 20.2 fb −1−1 of ATLAS data from 8 TeV proton–proton collisions in Run 1 of the LHC. The algorithm removes calorimeter energy deposits due to charged hadrons from consideration during jet reconstruction, instead using measurements of their momenta from th...

The reconstruction of the signal from hadrons and jets emerging from the proton–proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electroma...

The production of a Z boson and a photon in association with a high-mass dijet system is studied using 20.2 fb−1 of proton-proton collision data at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV recorded with the ATLAS detector in 2012 at the Large Hadron Collider. Final states with a photon and a Z boson decaying into a pair of either electrons,...

Contrary to past high energy colliders, the LHC is a charge asymmetric machine. Therefore most of the hard scattering processes producing electrically charged final states have a positive integral charge asymmetry. The latter quantity, denoted AC (ℓ ±), is easily measurable in event topologies bearing an odd number of hard and isolated charged lept...

Two-particle pseudorapidity correlations are measured in sNN=2.76TeVPb+Pb, sNN=5.02TeVp+Pb, and s=13TeVpp collisions at the Large Hadron Collider (LHC), with total integrated luminosities of approximately 7μb-1, 28 nb-1, and 65 nb-1, respectively. The correlation function CN(η1,η2) is measured as a function of event multiplicity using charged parti...

Multi-particle cumulants and corresponding Fourier harmonics are measured for azimuthal angle distributions of charged particles in pppp collisions at s√s = 5.02 and 13 TeV and in pp + Pb collisions at sNN−−−√sNN = 5.02 TeV, and compared to the results obtained for low-multiplicity Pb + PbPb + Pb collisions at sNN−−−√sNN = 2.76 TeV. These measureme...

Measurements of the production cross section of a ZZ boson in association with jets in proton–proton collisions at s√=13s=13 TeV are presented, using data corresponding to an integrated luminosity of 3.16 fb −1−1 collected by the ATLAS experiment at the CERN Large Hadron Collider in 2015. Inclusive and differential cross sections are measured for e...

High-precision measurements by the ATLAS Collaboration are presented of inclusive W+→ℓ+νW+→ℓ+ν , W−→ℓ−ν¯W−→ℓ−ν¯ and Z/γ∗→ℓℓZ/γ∗→ℓℓ ( ℓ=e,μℓ=e,μ ) Drell–Yan production cross sections at the LHC. The data were collected in proton–proton collisions at s√=7TeVs=7TeV with an integrated luminosity of 4.6fb−14.6fb−1 . Differential W+W+ and W−W− cross sect...

A measurement of the production cross section for two isolated photons in proton-proton collisions at a center-of-mass energy of s=8 TeV is presented. The results are based on an integrated luminosity of 20.2 fb-1 recorded by the ATLAS detector at the Large Hadron Collider. The measurement considers photons with pseudorapidities satisfying |ηγ|<1.3...

The tracking performance parameters of the ATLAS Transition Radiation Tracker (TRT) as part of the ATLAS inner detector are described in this paper for different data-taking conditions in proton-proton, proton-lead and lead-lead collisions at the Large Hadron Collider (LHC). The performance is studied using data collected during the first period of...

Measurements of jet activity in top-quark pair events produced in proton–proton collisions are presented, using 3.2 fb−1 of pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an oppositecharge eμ pair and two b-tagged jets in the final state. The norm...

Measurements of jet activity in top-quark pair events produced in proton–proton collisions are presented, using 3.2 fb−1−1 of pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an opposite-charge eμeμ pair and two b-tagged jets in the final state. The...

Measurements of jet activity in top-quark pair events produced in proton–proton collisions are presented, using 3.2 fb\(^{-1}\) of pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an opposite-charge \(e\mu \) pair and two b-tagged jets in the final...

The reconstruction and calibration algorithms used to calculate missing transverse momentum (\(E_{\text {T}}^{\text {miss}}\) ) with the ATLAS detector exploit energy deposits in the calorimeter and tracks reconstructed in the inner detector as well as the muon spectrometer. Various strategies are used to suppress effects arising from additional pr...

A measurement of the t-channel single-top-quark and single-top-antiquark production cross-sections in the lepton+jets channel is presented, using 3.2 fb−1 of proton-proton collision data at a centre-of-mass energy of 13 TeV, recorded with the ATLAS detector at the LHC in 2015. Events are selected by requiring one charged lepton (electron or muon),...

This paper presents a measurement of the polarisation of W bosons from \(t\bar{t}\) decays, reconstructed in events with one high-\(p_{\text{ T }}\) lepton and at least four jets. Data from pp collisions at the LHC were collected at \(\sqrt{s}\) = 8 TeV and correspond to an integrated luminosity of 20.2 fb\(^{-1}\). The angle \(\theta ^{*}\) betwee...

To probe the W tb vertex structure, top-quark and W -boson polarisation observables are measured from t-channel single-top-quark events produced in proton-proton collisions at a centre-of-mass energy of 8 TeV. The dataset corresponds to an integrated luminosity of 20.2 fb−1, recorded with the ATLAS detector at the LHC. Selected events contain one i...

This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 pp collision data produced by the LHC at s√ = 8 TeV. The efficiency o...

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...

This paper reports a search for triboson \(W^{\pm }W^{\pm }W^{\mp }\) production in two decay channels (\({W^{\pm }W^{\pm }W^{\mp } \rightarrow \ell ^\pm \nu \ell ^\pm \nu \ell ^\mp \nu }\) and \({W^{\pm }W^{\pm }W^{\mp } \rightarrow \ell ^\pm \nu \ell ^\pm \nu jj}\) with \(\ell =e, \mu \)) in proton-proton collision data corresponding to an integr...

Two searches for new phenomena in final states containing a same-flavour opposite-sign lepton (electron or muon) pair, jets, and large missing transverse momentum are presented. These searches make use of proton–proton collision data, collected during 2015 and 2016 at a centre-of-mass energy \(\sqrt{s}=13\) \(\text {TeV}\) by the ATLAS detector at...

This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 pp collision data produced by the LHC at \(\sqrt{\mathrm {s}}\) = 8 \...

Ratios of top-quark pair to Z-boson cross sections measured from protonproton collisions at the LHC centre-of-mass energies of √ s = 13 TeV, 8 TeV, and 7 TeV are presented by the ATLAS Collaboration. Single ratios, at a given √ s for the two processes and at different √ s for each process, as well as double ratios of the two processes at different...

A search is presented for anomalous quartic gauge boson couplings in vector-boson scattering. The data for the analysis correspond to 20.2 fb−1 of ffiffi s p ¼ 8 TeV pp collisions and were collected in 2012 by the ATLAS experiment at the Large Hadron Collider. The search looks for the production of WW or WZ boson pairs accompanied by a high-mass di...

Same- and opposite-sign charge asymmetries are measured in lepton+jets \( t\overline{t} \) events in which a b-hadron decays semileptonically to a soft muon, using data corresponding to an integrated luminosity of 20.3 fb−1 from proton-proton collisions at a centre-of-mass energy of \( \sqrt{s}=8 \) TeV collected with the ATLAS detector at the Larg...

Ratios of top-quark pair to Z-boson cross sections measured from proton-proton collisions at the LHC centre-of-mass energies of s=13 TeV, 8 TeV, and 7 TeV are presented by the ATLAS Collaboration. Single ratios, at a given s for the two processes and at different s for each process, as well as double ratios of the two processes at different s, are...

Differential cross sections are presented for the prompt and non-prompt production of the hidden-charm states X(3872) and ψ(2S), in the decay mode J/ψπ+π−, measured using 11.4 fb−1 of pp collisions at \( \sqrt{s}=8 \) TeV by the ATLAS detector at the LHC. The ratio of cross-sections X(3872)/ψ(2S) is also given, separately for prompt and non-prompt...

Differential cross sections are presented for the prompt and non-prompt production of the hidden-charm states X(3872) and ψ(2S), in the decay mode J/ψπ+π −, measured using 11.4 fb−1 of pp collisions at √ s = 8 TeV by the ATLAS detector at the LHC. The ratio of cross-sections X(3872)/ψ(2S) is also given, separately for prompt and nonprompt component...

A measurement of the ZZ production cross section in the ℓ−ℓ+ℓ′ −ℓ′ + and ℓ−ℓ+νν¯¯¯ℓ−ℓ+νν¯ channels (ℓ = e, μ) in proton-proton collisions at s√=8s=8 TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb−1 collected by the ATLAS experiment in 2012 is presented. The fiducial cross sections for ZZ →...

A measurement of the calorimeter response to isolated charged hadrons in the ATLAS detector at the LHC is presented. This measurement is performed with 3.2 nb −1−1 of proton–proton collision data at s√=7s=7 TeVTeV from 2010 and 0.1 nb −1−1 of data at s√=8s=8 TeVTeV from 2012. A number of aspects of the calorimeter response to isolated hadrons are e...

A measurement of the calorimeter response to isolated charged hadrons in the ATLAS detector at the LHC is presented. This measurement is performed with 3.2 nb\(^{-1}\) of proton–proton collision data at \(\sqrt{s}=7\) \(\,\mathrm{TeV}\) from 2010 and 0.1 nb\(^{-1}\) of data at \(\sqrt{s}=8\) \(\,\mathrm{TeV}\) from 2012. A number of aspects of the...

A measurement of the \(t\bar{t}Z\) and \(t\bar{t}W\) production cross sections in final states with either two same-charge muons, or three or four leptons (electrons or muons) is presented. The analysis uses a data sample of proton–proton collisions at \(\sqrt{s} = 13\) TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015, corr...

A measurement of the ZZ production cross section in the ℓ−ℓ+ℓ′ −ℓ′ + and \( {\ell}^{-}{\ell}^{+}\nu \overline{\nu} \) channels (ℓ = e, μ) in proton-proton collisions at \( \sqrt{s}=8 \)TeV at the Large Hadron Collider at CERN, using data corresponding to an integrated luminosity of 20.3 fb−1 collected by the ATLAS experiment in 2012 is presented. T...

The W boson angular distribution in events with high transverse momentum jets is measured using data collected by the ATLAS experiment from proton–proton collisions at a centre-of-mass energy s=8 TeVat the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb−1. The focus is on the contributions to W+ jetsprocesses from real W...

The luminosity determination for the ATLAS detector at the LHC during pp collisions at \(\sqrt{s} =\) 8 TeV in 2012 is presented. The evaluation of the luminosity scale is performed using several luminometers, and comparisons between these luminosity detectors are made to assess the accuracy, consistency and long-term stability of the results. A lu...

A test of CP invariance in Higgs boson production via vector-boson fusion using the method of the Optimal Observable is presented. The analysis exploits the decay mode of the Higgs boson into a pair of \(\tau \) leptons and is based on 20.3 \(\mathrm{fb}^{-1}\) of proton–proton collision data at \(\sqrt{s}\) = 8 \(\,\mathrm{TeV}\) collected by the...

The algorithms used by the ATLAS Collaboration to reconstruct and identify prompt photons are described. Measurements of the photon identification efficiencies are reported, using 4.9 fb\(^{-1}\) of pp collision data collected at the LHC at \(\sqrt{s} = 7\) \(\text {TeV}\) and 20.3 fb\(^{-1}\) at \(\sqrt{s} = 8\) \(\text {TeV}\). The efficiencies a...

The dijet production cross section for jets containing a b-hadron (b-jets) has been measured in proton–proton collisions with a centre-of-mass energy of \(\sqrt{s} = 7\) TeV, using the ATLAS detector at the LHC. The data used correspond to an integrated luminosity of \(\mathrm 4.2\,\text {fb}^{-1}\). The cross section is measured for events with tw...

A search for supersymmetry in events with large missing transverse momentum, jets, and at least one hadronically decaying tau lepton has been performed using 3.2 fb\(^{-1}\) of proton–proton collision data at \(\sqrt{s}=13{\mathrm {\ TeV}}\) recorded by the ATLAS detector at the Large Hadron Collider in 2015. Two exclusive final states are consider...

The dijet production cross section for jets containing a b-hadron (b-jets) has been measured in proton– proton collisions with a centre-of-mass energy of √s = 7 TeV, using the ATLAS detector at the LHC. The data used correspond to an integrated luminosity of 4.2 fb−1. The cross section is measured for events with two identified b-jets with a transv...

Knowledge of the material in the ATLAS inner tracking detector is crucial in understanding the reconstruction of charged-particle tracks, the performance of algorithms that identify jets containing b-hadrons and is also essential to reduce background in searches for exotic particles that can decay within the inner detector volume. Interactions of p...

Knowledge of the material in the ATLAS inner tracking detector is crucial in understanding the reconstruction of charged-particle tracks, the performance of algorithms that identify jets containing b-hadrons and is also essential to reduce background in searches for exotic particles that can decay within the inner detector volume. Interactions of p...

A search is presented for new resonances decaying to a W or Z boson and a Higgs boson in the ℓ+ℓ−bb¯, ℓνbb¯, and νν¯bb¯ channels in pp collisions at s=13 TeV with the ATLAS detector at the Large Hadron Collider using a total integrated luminosity of 3.2 fb⁻¹. The search is conducted by looking for a localized excess in the WH/ZH invariant or transv...

A search for dark matter pair production in association with a Higgs boson decaying to a pair of bottom quarks is presented, using 3.2 fb⁻¹ of pp collisions at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the LHC. The decay of the Higgs boson is reconstructed as a high-momentum bb¯ system with either a pair of small-radius j...

This Letter presents a search for new resonances with mass larger than 250 GeV, decaying to a Z boson and a photon. The dataset consists of an integrated luminosity of 3.2 fb⁻¹ of pp collisions collected at s=13 TeV with the ATLAS detector at the Large Hadron Collider. The Z bosons are identified through their decays either to charged, light, lepto...

Measurements of normalized differential cross sections of top quark pair (tt production are presented as a function of the mass, the transverse momentum and the rapidity of the tt system in proton-proton collisions at center-of-mass energies of s=7 and 8 TeV. The data set corresponds to an integrated luminosity of 4.6 fb-1 at 7 TeV and 20.2 fb-1 at...