Documents in process

The production of single top quarks and top antiquarks via the t-channel exchange of a virtual W boson is measured in proton--proton collisions at a centre-of-mass energy of 13 TeV at the Large Hadron Collider. The full Run 2 data samples recorded with the ATLAS detector in the years 2015-2018 is used, corresponding to an integrated luminosity of 140 fb−1. [...]

In July 2025, the LHC delivered oxygen-oxygen (O+O) collisions at 5.36 TeV, and the ATLAS experiment collected 8 nb$^{-1}$ of data. This dataset offers a unique opportunity to search for the onset of energy loss effects in a small collision system comparable in transverse size to peripheral Pb+Pb collisions. [...]

A measurement is presented of $t\bar{t}$ production in the invariant-mass region near the pair production threshold,$m_{t\bar{t}}$∼345GeV, in final states with two charged leptons and multiple jets. The measurement is based on 140fb$^{-1}$ of proton–proton collision data collected at $\sqrt{s}$=13TeV with the ATLAS detector. [...]

Higgs boson production cross-sections are measured in the $H\rightarrow~ZZ^\ast\rightarrow~4\ell$ decay channel based on 56 fb$^{-1}$ of proton-proton collision data produced at the Large Hadron Collider at a centre-of-mass energy of 13.6 TeV and recorded by the ATLAS detector in 2022 and 2023. Inclusive fiducial and total cross-sections are measured in addition to differential cross-sections for the four-lepton transverse momentum and rapidity, the invariant mass of the off-shell lepton pair and the jet multiplicity. [...]

The measurements of the cross sections for Zγ production and the search for neutral triple gauge couplings (nTGC) through ZZγ or γ∗Zγ vertices are presented, using the full Run2 proton-proton dataset of 140 fb−1 produced by the LHC at √s = 13 TeV and collected by the ATLAS detector. Kinematic distributions are measured using events with a Z boson candidate decaying into either an e+e− or μ+μ− pair and a photon. [...]

This study presents differential fiducial cross-section measurements of photon-induced $\tau$-lepton pair production. The results are obtained using ultraperipheral lead-lead collisions recorded in 2015 and 2018 at $\sqrt{s_{_\text{NN}}} = 5.02$ TeV by the ATLAS experiment at the LHC. [...]

Measurements of jet substructure in Pb+Pb collisions provide key insights into the mechanism of jet quenching in the hot and dense QCD medium created in these collisions.This Letter presents a measurement of the suppression of large-radius jets with a radius parameter of R=1.0 and its dependence on the jet substructure. The measurement uses 1.72 nb−1 of Pb+Pb data and 255 pb−1 of pp data, both at sNN=5.02 TeV, recorded with the ATLAS detector at the Large Hadron Collider. [...]

A search for the dimuon decay of the Higgs boson is presented based on pp collision data recorded by ATLAS during Run 3 of the Large Hadron Collider, corresponding to an integrated luminosity of 165 fb-1 at s=13.6 TeV. To enhance the sensitivity, the results are combined with those from Run 2. [...]