Search for heavy neutral leptons in decays of W bosons produced in 13 TeV p p collisions using prompt and displaced signatures with the ATLAS detectorThe ATLAS CollaborationThe problems of neutrino masses, matter-antimatter asymmetry, and dark matter could be successfully addressed by postulating right-handed neutrinos with Majorana masses below the electroweak scale. In this work, leptonic decays of W bosons extracted from 32.9 fb −1 to 36.1 fb −1 of 13 TeV proton-proton collisions at the LHC are used to search for heavy neutral leptons (HNLs) that are produced through mixing with muon or electron neutrinos. The search is conducted using the ATLAS detector in both prompt and displaced leptonic decay signatures. The prompt signature requires three leptons produced at the interaction point (either µµe or eeµ) with a veto on same-flavour opposite-charge topologies. The displaced signature comprises a prompt muon from the W boson decay and the requirement of a dilepton vertex (either µµ or µe) displaced in the transverse plane by 4-300 mm from the interaction point. The search sets constraints on the HNL mixing to muon and electron neutrinos for HNL masses in the range 4.5-50 GeV.

Narrow resonances decaying into W W , W Z or ZZ boson pairs are searched for in 139 fb −1 of proton-proton collision data at a centre-of-mass energy of √ s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider from 2015 to 2018. The diboson system is reconstructed using pairs of high transverse momentum, large-radius jets. These jets are built from a combination of calorimeter-and tracker-inputs compatible with the hadronic decay of a boosted W or Z boson, using jet mass and substructure properties. The search is performed for diboson resonances with masses greater than 1.3 TeV. No significant deviations from the background expectations are observed. Exclusion limits at the 95% confidence level are set on the production cross-section times branching ratio into dibosons for resonances in a range of theories beyond the Standard Model, with the highest excluded mass of a new gauge boson at 3.8 TeV in the context of mass-degenerate resonances that couple predominantly to gauge bosons.

Allergic diseases, such as asthma, rhinitis, dermatitis, conjunctivitis, and anaphylaxis, have recently become a global public health concern. According to previous studies, the NLRP3 inflammasome is a multi-protein complex known to be associated with many inflammatory conditions. In response to allergens or allergen/damage-associated molecular signals, NLRP3 changes its conformation to allow the assembly of the NLRP3 inflammasome complex and activates caspase-1, which is an evolutionarily conserved enzyme that proteolytically cleaves other proteins, such as the precursors of the inflammatory cytokines IL-1β and IL-18. Subsequently, active caspase-1 cleaves pro-IL-1 and pro-IL-18. Recently, accumulating human and mouse experimental evidence has demonstrated that the NLRP3 inflammasome, IL-1β, and IL-18 are critically involved in the development of allergic diseases. Furthermore, the application of specific NLRP3 inflammasome inhibitors has been demonstrated in animal models. Therefore, these inhibitors may represent potential therapeutic methods for the management of clinical allergic disorders. This review summarizes findings related to the NLRP3 inflammasome and its related factors and concludes that specific NLRP3 inflammasome inhibitors may be potential therapeutic agents for allergic diseases.

The ATLAS CollaborationA search for vectorlike quarks is presented, which targets their decay into a Z boson and a third-generation Standard Model quark. In the case of a vectorlike quark T (B) with charge + 2 /3e (− 1 /3e), the decay searched for is T → Zt (B → Z b). Data for this analysis were taken during 2015 and 2016 with the ATLAS detector at the Large Hadron Collider and correspond to an integrated luminosity of 36.1 fb −1 of pp collisions at √ s = 13 TeV. The final state used is characterized by the presence of b-tagged jets, as well as a Z boson with high transverse momentum, which is reconstructed from a pair of opposite-sign same-flavor leptons. Pair and single production of vectorlike quarks are both taken into account and are each searched for using optimized dileptonic exclusive and trileptonic inclusive event selections. In these selections, the high scalar sum of jet transverse momenta, the presence of high-transversemomentum large-radius jets, as well as-in the case of the single-production selections-the presence of forward jets are used. No significant excess over the background-only hypothesis is found and exclusion limits at 95% confidence level allow masses of vectorlike quarks of m T > 1030 GeV (m T > 1210 GeV) and m B > 1010 GeV (m B > 1140 GeV) in the singlet (doublet) model. In the case of 100% branching ratio for T → Zt (B → Z b), the limits are m T > 1340 GeV (m B > 1220 GeV). Limits at 95% confidence level are also set on the coupling to Standard Model quarks for given vectorlike quark masses.

Measurement of inclusive jet and dijet cross-sections in proton proton collisions at√ s = 13 TeV with the ATLAS detectorThe ATLAS Collaboration Inclusive jet and dijet cross-sections are measured in proton proton collisions at a centreof-mass energy of 13 TeV. The measurement uses a dataset with an integrated luminosity of 3.2 fb −1 recorded in 2015 with the ATLAS detector at the Large Hadron Collider. Jets are identified using the anti-k t algorithm with a radius parameter value of R = 0.4. The inclusive jet cross-sections are measured double-differentially as a function of the jet transverse momentum, covering the range from 100 GeV to 3.5 TeV, and the absolute jet rapidity up to |y| = 3. The double-differential dijet production cross-sections are presented as a function of the dijet mass, covering the range from 300 GeV to 9 TeV, and the half absolute rapidity separation between the two leading jets within |y| < 3, y * , up to y * = 3. Next-to-leading-order, and next-to-next-to-leading-order for the inclusive jet measurement, perturbative QCD calculations corrected for non-perturbative and electroweak effects are compared to the measured cross-sections.The ATLAS experiment [19,20] at the LHC is a multi-purpose particle detector with a forward-backward symmetric cylindrical geometry and a near 4π coverage in solid angle. 3 It consists of an inner tracking detector, electromagnetic and hadron calorimeters, and a muon spectrometer. The inner tracking detector covers the pseudorapidity range |η| < 2.5 and is used to reconstruct tracks and vertices. It consists of silicon pixel, silicon microstrip, and transition radiation tracking detectors, surrounded by a thin superconducting solenoid providing a 2 T axial magnetic field. Lead/liquid-argon (LAr) sampling calorimeters provide electromagnetic (EM) energy measurements with high granularity. They consist of a barrel (|η| < 1.475) and two endcap (1.375 ≤ |η| < 3.2) regions. The hadron calorimeters are divided into five distinct regions: a barrel region (|η| < 0.8), two extended barrel regions (0.8 ≤ |η| < 1.7) and two endcap regions (1.5 ≤ |η| < 3.2). The barrel and extended barrel regions are instrumented with steel/scintillator tile calorimeters. The endcap regions are instrumented with LAr calorimeters for both the EM and hadronic energy measurements. The ATLAS calorimeters have very high lateral granularity and several samplings in depth over |η| < 3.2. The muon spectrometer surrounds the calorimeters and features three large air-core toroid superconducting magnets with eight coils each. The field integral of the toroids ranges between 2.0 and 6.0 Tm across most of the detector. It includes a system of precision tracking chambers for track measurement in the principal bending direction and fast detectors for triggering and measurement of the muon coordinate in the direction orthogonal to that determined by the precision-tracking chambers. A two-level trigger system is used to select events. The first-level trigger is implemented in hardware and uses a subset of t...