Model-independent search for the presence of new physics in events including H → γγ with s \sqrt{s} = 13 TeV pp data recorded by the ATLAS detector at the LHC

Abstract A model-independent search for new physics leading to final states containing a Higgs boson, with a mass of 125.09 GeV, decaying to a pair of photons is performed with 139 fb−1 of s $$\sqrt{s}$$ = 13 TeV pp collision data recorded by the ATLAS detector at the Large Hadron Collider at CERN. This search examines 22 final states categorized by the objects that are produced in association with the Higgs boson. These objects include isolated electrons or muons, hadronically decaying τ-leptons, additional photons, missing transverse momentum, and hadronic jets, as well as jets that are tagged as containing a b-hadron. No significant excesses above Standard Model expectations are observed and limits on the production cross section at 95% confidence level are set. Detector efficiencies are reported for all 22 signal regions, which can be used to convert detector-level cross-section limits reported in this paper to particle-level cross-section constraints

Combination of the W boson polarization measurements in top quark decays using ATLAS and CMS data at s = 8 TeV

Abstract: 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 a centre-of-mass energy of 8 TeV, and corresponding to an integrated luminosity of about 20 fb−1 for each experiment. The measurements used events containing one lepton and having different jet multiplicities in the final state. The results are quoted as fractions of W bosons with longitudinal (F0), left-handed (FL), or right-handed (FR) polarizations. The resulting combined measurements of the polarization fractions are F0 = 0.693 ± 0.014 and FL = 0.315 ± 0.011. The fraction FR is calculated from the unitarity constraint to be FR = −0.008 ± 0.007. These results are in agreement with the standard model predictions at next-to-next-to-leading order in perturbative quantum chromodynamics and represent an improvement in precision of 25 (29)% for F0 (FL) with respect to the most precise single measurement. A limit on anomalous right-handed vector (VR), and left- and right-handed tensor (gL, gR) tWb couplings is set while fixing all others to their standard model values. The allowed regions are [−0.11, 0.16] for VR, [−0.08, 0.05] for gL, and [−0.04, 0.02] for gR, at 95% confidence level. Limits on the corresponding Wilson coefficients are also derived

Mean-Field Limits for Entropic Multi-Population Dynamical Systems

The well-posedness of a multi-population dynamical system with an entropy regularization and its convergence to a suitable mean-field approximation are proved, under a general set of assumptions. Under further assumptions on the evolution of the labels, the case of different time scales between the agents' locations and labels dynamics is considered. The limit system couples a mean-field-type evolution in the space of positions and an instantaneous optimization of the payoff functional in the space of labels

Is there such thing as 'populist constitutionalism'? : the case of Hungary

First online: 06 February 2018The paper deals with recent deviations from the shared values of constitutionalism towards a kind of 'populist, illiberal constitutionalism' introduced by Hungary's new constitution in 2011. The populism of FIDESZ was directed against all elites, including the ones that designed the 1989 constitutional system (in which FIDESZ also participated), claiming that it was time for a new revolution. This is why PM Viktor Orban characterized the results of the 2010 elections as a 'revolution of the ballot boxes'. His intention with this revolution was to eliminate all checks and balances, and even the parliamentary rotation of governing parties. His vision for a new constitutional order-one in which his political party occupies the centre stage of Hungarian political life and puts an end to debates over values-has now been entrenched in the new constitution. The paper argues that this current Hungarian constitutional system was made possible by FIDESZ' anti-pluralist nationalist populism, but is not necessarily based on a true commitment to expressing the will of the people via 'illiberal constitutionalism'. The populist government rather misuses the country's lack of constitutional culture. Adherence to constitutional patriotism would mean that FIDESZ would have to endorse what John Rawls once called 'constitutional essentials'. The core of this kind of constitutional patriotism is a constitutional culture centred on universalist liberal democratic norms and values. Instead, the current Hungarian constitutional system is confronted with unconstitutional patriotism, a kind of nationalism that violates constitutional essentials in the name of 'national constitutional identity'