Measurement of single top-quark production in association with a W boson in the single-lepton channel at \sqrt{s} = 8\,\text {TeV} with the ATLAS detector

The production cross-section of a top quark in association with a W boson is measured using proton–proton collisions at \sqrt{s} = 8\,\text {TeV}. The dataset corresponds to an integrated luminosity of 20.2\,\text {fb}^{-1}, and was collected in 2012 by the ATLAS detector at the Large Hadron Collider at CERN. The analysis is performed in the single-lepton channel. Events are selected by requiring one isolated lepton (electron or muon) and at least three jets. A neural network is trained to separate the tW signal from the dominant t{\bar{t}} background. The cross-section is extracted from a binned profile maximum-likelihood fit to a two-dimensional discriminant built from the neural-network output and the invariant mass of the hadronically decaying W boson. The measured cross-section is \sigma _{tW} = 26 \pm 7\,\text {pb}, in good agreement with the Standard Model expectation

Italian Identity in the United States

none1siItaly’s belated completion of political unification in 1861 let the Italian people long retain a regional, provincial, and even local identity. Likewise, the newcomers who arrived in the United States from different places in Italy between the late 1870s and the closing of mass immigration in the mid-1920s found it difficult to perceive themselves as members of the same ethnic minority and shied away from one another not only in areas of residence but also in social and religious life at the beginning of their stay in America. By the late 1930s, however, the emergence and consolidation of nationalistic feelings, following both Italy’s entry into World War I and Fascist aggressive foreign policy, immigration restriction, the appearance of a US-born second generation with loose ties to the forebears’ land, and, primarily, the experience of anti-Italian intolerance and discrimination in the United States made people of Italian descent aware of their common national ancestry and helped them develope an Italian identity that they or their parents had lacked upon settling in the United States. Racial tensions and the backlash at blacks’ supposed encroachments in the postwar decades encouraged many Italian Americans to join forces with other immigrant groups of European origin from which they had previously distanced themselves. They, therefore, acquired a racial sense of belonging as white Europeans and nowadays retain an Italian identity only at a symbolic level, almost exclusively in leisure time activities.embargoed_20220710LUCONI, StefanoLuconi, Stefan

Search for heavy ZZ resonances in the +−+− and +−νν¯ final states using proton–proton collisions at √s = 13 TeV with the ATLAS detector

A search for heavy resonances decaying into a pair of Z bosons leading to +−+− and +−νν¯ final states, where stands for either an electron or a muon, is presented. The search uses proton–proton collision data at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider. Different mass ranges for the hypothetical resonances are considered, depending on the final state and model. The different ranges span between 200 and 2000 GeV. The results are interpreted as upper limits on the production cross section of a spin-0 or spin-2 resonance. The upper limits for the spin-0 resonance are translated to exclusion contours in the context of Type-I and Type-II two-Higgs-doublet models, while those for the spin-2 resonance are used to constrain the Randall–Sundrum model with an extra dimension giving rise to spin-2 graviton excitations