Electron and photon triggers covering transverse energies from 5 GeV to several TeV are essential for the ATLAS experiment to record signals for a wide variety of physics: from Standard Model processes to searches for ...

Searches for the Higgs boson decays H→ee and H→eμ are performed using data corresponding to an integrated luminosity of 139fb−1 collected with the ATLAS detector in ppcollisions at √s=13TeV at the LHC. No significant signals ...

Multi-particle azimuthal cumulants are measured as a function of centrality and transverse momentum using 470 μb−1 of Pb+Pb collisions at sNN−−−√ = 5.02 TeV with the ATLAS detector at the LHC. These cumulants provide ...

Azimuthal anisotropies of muons from charm and bottom hadron decays are measured in Pb+Pb collisions at √sNN=5.02TeV. The data were collected with the ATLAS detector at the Large Hadron Collider in 2015 and 2018 with ...

A measurement of the production of a prompt J/ψ meson in association with a W± boson with W± → μν and J/ψ → μ+μ− is presented for J/ψ transverse momenta in the range 8.5–150 GeV and rapidity |yJ/ψ| < 2.1 using ATLAS data ...

The production of a prompt photon in association with a Z boson is studied in proton-proton collisions at a centre-of-mass energy s√ = 13 TeV. The analysis uses a data sample with an integrated luminosity of 139 fb−1 ...

This paper presents results of searches for the electroweak production of supersymmetric particles in models with compressed mass spectra. The searches use 139  fb−1 of √s=13  TeV proton-proton collision data collected by ...

A dedicated sample of Large Hadron Collider proton-proton collision data at centre-of-mass energy s√ = 8 TeV is used to study inclusive single diffractive dissociation, pp → X p. The intact final-state proton is reconstructed ...

The elliptic flow of muons from the decay of charm and bottom hadrons is measured in pp collisions at √s=13  TeV using a data sample with an integrated luminosity of 150  pb−1 recorded by the ATLAS detector at the LHC. The ...

Several models of physics beyond the Standard Model predict the existence of dark photons, light neutral particles decaying into collimated leptons or light hadrons. This paper presents a search for long-lived dark photons ...

The production yield of Z bosons is measured in the electron and muon decay channels in Pb+Pb collisions at √sNN=5.02 TeV with the ATLAS detector. Data from the 2015 LHC run corresponding to an integrated luminosity of ...

This paper presents a measurement of the production cross-section of a Z boson in association with b-jets, in proton-proton collisions at s√ = 13 TeV with the ATLAS experiment at the Large Hadron Collider using data ...

This paper describes precision measurements of the transverse momentum pℓℓT (ℓ=e,μ) and of the angular variable ϕ∗η distributions of Drell–Yan lepton pairs in a mass range of 66–116 GeV. The analysis uses data from 36.1 ...

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 ...

We characterized the pulsed Rydberg-positronium production inside the Antimatter Experiment: Gravity, Interferometry, Spectroscopy (AE¯gIS) apparatus in view of antihydrogen formation by means of a charge exchange reaction ...

The performance of the ATLAS muon trigger system is evaluated with proton-proton (pp) and heavy-ion (HI) collision data collected in Run 2 during 2015–2018 at the Large Hadron Collider. It is primarily evaluated using ...

The combination of measurements of the W boson polarization in top quark decays performed by the ATLAS and CMS collaborations is presented. The measurements are based on proton-proton collision data produced at the LHC at ...

The prevalence of hadronic jets at the LHC requires that a deep understanding of jet formation and structure is achieved in order to reach the highest levels of experimental and theoretical precision. There have been many ...

A search for flavour-changing neutral current (FCNC) events via the coupling of a top quark, a photon, and an up or charm quark is presented using 81fb−1of proton–proton collision data taken at a centre-of-mass energy of ...

A search for new resonances decaying into a pair of jets is reported using the dataset of proton-proton collisions recorded at s√ = 13 TeV with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, ...

This paper describes a search for beyond the Standard Model decays of the Higgs boson into a pair of new spin-0 particles subsequently decaying into b-quark pairs, H→aa→(b¯b)(b¯b), using proton-proton collision data collected ...

A search for new physics with non-resonant signals in dielectron and dimuon final states in the mass range above 2 TeV is presented. This is the first search for non-resonant signals in dilepton final states at the LHC to ...

A search is presented for four-top-quark production using an integrated luminosity of 139 fb−1 of proton–proton collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the LHC. Events are ...

The performance of the ATLAS Inner Detector alignment has been studied using pp collision data at s√=13TeV collected by the ATLAS experiment during Run 2 (2015–2018) of the Large Hadron Collider (LHC). The goal of the ...

A search is presented for pair production of long-lived neutral particles using 33  fb−1 of √s=13  TeV proton–proton collision data, collected during 2016 by the ATLAS detector at the LHC. This search focuses on a topology ...

The dynamics of isolated-photon plus two-jet production in pp collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset corresponding to an integrated luminosity of 36.1 ...

The inclusive top quark pair (tt¯) production cross-section σtt¯ has been measured in proton–proton collisions at s√=13TeV, using 36.1 fb−1 of data collected in 2015–2016 by the ATLAS experiment at the LHC. Using events ...

A measurement of observables sensitive to spin correlations in tt¯ production is presented, using 36.1 fb−1 of pp collision data at s√=13 TeV recorded with the ATLAS detector at the Large Hadron Collider. Differential ...

A search for the direct production of the supersymmetric partners of τ-leptons (staus) in final states with two hadronically decaying τ-leptons is presented. The analysis uses a dataset of pp collisions corresponding to ...

In this paper, a new technique for reconstructing and identifying hadronically decaying τ+τ− pairs with a large Lorentz boost, referred to as the di-τ tagger, is developed and used for the first time in the ATLAS experiment ...

This paper presents a search for direct top squark pair production in events with missing transverse momentum plus either a pair of jets consistent with Standard Model Higgs boson decay into b-quarks or a same-flavour ...

A bstract The factor of four increase in the LHC luminosity, from 0 . 5 × 10 34 cm − 2 s − 1 to 2 . 0 × 10 34 cm − 2 s − 1 , and the corresponding increase in pile-up collisions during the 2015–2018 data-taking period, ...

Jet substructure quantities are measured using jets groomed with the soft-drop grooming procedure in dijet events from 32.9  fb−1 of pp collisions collected with the ATLAS detector at √s=13  TeV. These observables are ...

The azimuthal anisotropy of charged particles produced in sNN−−−√=8.16 TeV p+Pb collisions is measured with the ATLAS detector at the LHC. The data correspond to an integrated luminosity of 165 nb−1 that was collected in ...

A search for magnetic monopoles and high-electric-charge objects is presented using 34.4  fb−1 of 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015 and 2016. The considered signature is based ...

Combined measurements of Higgs boson production cross sections and branching fractions are presented. The combination is based on the analyses of the Higgs boson decay modes H→γγ, ZZ∗, WW∗, ττ, b¯b, μμ, searches for decays ...

A search for heavy neutral Higgs bosons is performed using the LHC Run 2 data, corresponding to an integrated luminosity of 139  fb−1 of proton-proton collisions at √s=13  TeV recorded with the ATLAS detector. The search ...

The PreProcessor of the ATLAS Level-1 Calorimeter Trigger prepares the analogue trigger signals sent from the ATLAS calorimeters by digitising, synchronising, and calibrating them to reconstruct transverse energy deposits, ...

A search for supersymmetric partners of gluons and quarks is presented, involving signatures with jets and either two isolated leptons (electrons or muons) with the same electric charge, or at least three isolated leptons. ...

A study of the charge conjugation and parity (CP) properties of the interaction between the Higgs boson and top quarks is presented. Higgs bosons are identified via the diphoton decay channel (H→γγ), and their production ...

A search for heavy neutral Higgs bosons produced in association with one or two b-quarks and decaying to b-quark pairs is presented using 27.8  fb−1 of √s=13  TeV proton-proton collision data recorded by the ATLAS detector ...

A search for long-lived particles decaying into hadrons and at least one muon is presented. The analysis selects events that pass a muon or missing-transverse-momentum trigger and contain a displaced muon track and a ...

A search for dijet resonances in events with at least one isolated charged lepon is performed using 139 fb−1 of s√ = 13 TeV proton-proton collision data recorded by the ATLAS detector at the LHC. The dijet invariant-mass ...

A search for a chargino-neutralino pair decaying via the 125 GeV Higgs boson into photons is presented. The study is based on the data collected between 2015 and 2018 with the ATLAS detector at the LHC, corresponding to ...

Inclusive and differential fiducial cross sections of the Higgs boson are measured in the H→ZZ∗→4ℓ (ℓ=e,μ) decay channel. The results are based on proton-proton collision data produced at the Large Hadron Collider at a ...

A search for the electroweak production of charginos and sleptons decaying into final states with two electrons or muons is presented. The analysis is based on 139 fb−1 of proton–proton collisions recorded by the ATLAS ...

A search for heavy resonances decaying into a W or Z boson and a Higgs boson produced in proton−proton collisions at the Large Hadron Collider at √s=13  TeV is presented. The analysis utilizes the dominant W→q¯q′ or Z→q¯q ...

The ATLAS detector at the Large Hadron Collider reads out particle collision data from over 100 million electronic channels at a rate of approximately 100 kHz, with a recording rate for physics events of approximately 1 ...

This Letter presents a search for the production of new heavy resonances decaying into a Higgs boson and a photon using proton-proton collision data at √s=13  TeV collected by the ATLAS detector at the LHC. The data ...

The top anti-top quark production cross-section is measured in the lepton+jets channel using proton–proton collision data at a centre-of-mass energy of √s = 13 TeV collected with the ATLAS detector at the LHC. The dataset ...

A search for Higgs boson decays into a Z boson and a light resonance in two-lepton plus jet events is performed, using a pp collision dataset with an integrated luminosity of 139  fb−1 collected at √s=13  TeV by the ATLAS ...

A search for new-physics resonances decaying into a lepton and a jet performed by the ATLAS experiment is presented. Scalar leptoquarks pair-produced in pp collisions at s√ = 13 TeV at the Large Hadron Collider are considered ...

This paper presents a search for new heavy particles decaying into a pair of top quarks using 139 fb−1 of proton-proton collision data recorded at a centre-of-mass energy of s√ = 13 TeV with the ATLAS detector at the Large ...

From the experimental point of view, very little is known about the gravitational interaction between matter and antimatter. In particular, the Weak Equivalence Principle, which is of paramount importance for the General ...

This Letter describes a search for narrowly resonant new physics using a machine-learning anomaly detection procedure that does not rely on signal simulations for developing the analysis selection. Weakly supervised learning ...

Higgs boson properties are studied in the four-lepton decay channel (where lepton = e, μ) using 139 fb−1 of proton–proton collision data recorded at s√=13 TeV by the ATLAS experiment at the Large Hadron Collider. The ...

The observation of forward proton scattering in association with lepton pairs (e+e−+p or μ+μ−+p) produced via photon fusion is presented. The scattered proton is detected by the ATLAS Forward Proton spectrometer, while the ...

The algorithms used by the ATLAS Collaboration during Run 2 of the Large Hadron Collider to identify jets containing b-hadrons are presented. The performance of the algorithms is evaluated in the simulation and the efficiency ...

This paper presents a measurement of ZZ production with the ATLAS detector at the Large Hadron Collider. The measurement is carried out in the final state with two charged leptons and two neutrinos, using data collected ...

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 ...

Correlations of two flow harmonics and via three- and four-particle cumulants are measured in 13 TeV pp, 5.02 TeV p+Pb, and 2.76 TeV peripheral Pb+Pb collisions with the ATLAS detector at the LHC. The goal is to understand ...

Constraints on selected mediator-based dark matter models and a scalar dark energy model using up to 37 fb−1s√ = 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015-2016 are summarised in this ...

Results of a search for the pair production of photon-jets—collimated groupings of photons—in the ATLAS detector at the Large Hadron Collider are reported. Highly collimated photon-jets can arise from the decay of new, ...

This Letter presents a search for heavy charged long-lived particles produced in proton–proton collisions at at the LHC using a data sample corresponding to an integrated luminosity of collected by the ATLAS experiment ...

A search for a heavy charged-boson resonance decaying into a charged lepton (electron or muon) and a neutrino is reported. A data sample of 139  fb−1 of proton-proton collisions at √s=13  TeV collected with the ATLAS ...

An observation of electroweak W ± Z production in association with two jets in proton–proton collisions is presented. The data collected by the ATLAS detector at the Large Hadron Collider in 2015 and 2016 at a centre-of-mass ...

A search for heavy charged long-lived particles is performed using a data sample of 36.1  fb−1 of proton-proton collisions at √s=13  TeV collected by the ATLAS experiment at the Large Hadron Collider. The search is based ...

This paper presents measurements of the W+ → μ+ν and W− → μ−ν cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton– proton ...

This paper presents the electron and photon energy calibration obtained with the ATLAS detector using about 36 fb−1 of LHC proton-proton collision data recorded at √s=13 TeV in 2015 and 2016. The different calibration steps ...

A search for the production of three massive vector bosons in proton–proton collisions is performed using data at √s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider in the years 2015–2017, corresponding ...

This paper presents measurements of chargedparticle distributions sensitive to the properties of the underlying event in events containing a Z boson decaying into a muon pair. The data were obtained using the ATLAS detector ...

This paper presents the combinations of single-top-quark production cross-section measurements by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at s√ = 7 and 8 TeV corresponding to integrated ...

The inclusive production of four isolated charged leptons in pp collisions is analysed for the presence of hard double-parton scattering, using 20.2 fb−1 of data recorded in the ATLAS detector at the LHC at centre-of-mass ...

Dark matter particles, if sufficiently light, may be produced in decays of the Higgs boson. This Letter presents a statistical combination of searches for H→invisible decays where H is produced according to the standard ...

Searches for scalar leptoquarks pair-produced in proton–proton collisions at s√=13 TeV at the Large Hadron Collider are performed by the ATLAS experiment. A data set corresponding to an integrated luminosity of 36.1 fb−1 ...

A search for four-top-quark production, t¯tt¯t, is presented. It is based on proton-proton collision data with a center-of-mass energy √s=13  TeV collected by the ATLAS detector at the Large Hadron Collider during the years ...

A search for Higgs boson pair production in the bb¯¯WW∗ decay mode is performed in the bb¯¯ℓνqq final state using 36.1 fb−1 of proton-proton collision data at a centre-of-mass energy of 13 TeV recorded with the ATLAS ...

A measurement of jet substructure observables is presented using data collected in 2016 by the ATLAS experiment at the LHC with proton-proton collisions at s√ = 13 TeV. Large-radius jets groomed with the trimming and ...

A measurement of production cross sections of the Higgs boson in proton-proton collisions is presented in the H → ττ decay channel. The analysis is performed using 36.1 fb−1 of data recorded by the ATLAS experiment at the ...

The inclusive production rates of isolated, prompt photons in p + Pb collisions at √sNN = 8.16 TeV are studied with the ATLAS detector at the Large Hadron Collider using a dataset with an integrated luminosity of 165 nb−1 ...

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 √ s = 13 TeV delivered by the Large Hadron Collider. The ...

Jets created in association with a photon can be used as a calibrated probe to study energy loss in the medium created in nuclear collisions. Measurements of the transverse momentum balance between isolated photons and ...