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[en] A search for heavy resonances in final states with a Higgs boson and a vector boson is presented, performed in the data collected with the CMS detector at √s = 13TeV during 2015. The vector boson can be either a Z or W boson decaying leptonically (electrons, muons or neutrinos), whereas the Higgs boson decays hadronically into a couple of b-quarks of high momentum, detected as a single massive jet. The investigated final states consist of two b-quarks and zero, one or two charged leptons. Background shape and normalization are derived through a hybrid data-Monte Carlo method. The search is performed by examining the distribution of the reconstructed mass for a localized excess. Upper limits are derived as a function of the resonance mass and natural width, and are interpreted within the Heavy Vector Triplet theoretical model, as predicted in many scenarios beyond the standard model.
[en] Using a Luttinger liquid theory we investigate the time evolution of the particle density of a one-dimensional spinful fermionic system with open boundaries and subject to a finite-duration quench of the inter-particle interaction. Taking into account also the turning on of an umklapp perturbation to the system Hamiltonian as a result of the quench, we study the possible formation of a Wigner molecule inside the system, focusing in particular on the sudden and adiabatic regimes. We show that the creation of this correlated state is essentially due to the propagation of “light-cone” perturbations through the system which arise after both switching on and switching of the quenching protocol, and that its behavior strongly depends on the quench duration.
[en] The detection of continuous gravitational waves is among the main targets of the LIGO and Virgo detectors. Such kind of signals, emitted e.g. by spinning neutron stars asymmetric with respect to the rotation axis, are very weak and their search poses challenging data analysis problems. In this review I will discuss the main issues regarding the search of continuous gravitational waves in the data of current interferometric detectors and some recently published results.
[en] In this contribution we review our research activity with Roberto which focused mainly on the study of New Physics (NP) effects in Lepton Flavour Universality Violating (LFUV) observables such as RK = Γ( K → eν)/Γ(K →μν ). After reviewing our results, we discuss also the present status of LFUV in semileptonic B decays which is currently hinting to significant NP contributions.
[en] Angular distributions of transfer reaction "2"0"8Pb("7Li,"6He)"2"0"9Bi were measured at Elab("7Li)= 21.2, 24.3, 25.67 and 28.55 MeV. By fitting the experimental data with the theoretical frameworks of Distorted Wave Born Approximation (DWBA), the optical model parameters of the halo nuclear system "6He+"2"0"9Bi were extracted. The breakup threshold anomaly (BTA) was observed clearly in the imaginary potential, and a further decreasing trend in the deep sub-barrier region was observed for the first time in a halo system. Furthermore, the dispersion relation is found of no use to describe the connection between the real and imaginary parts
[en] RENO (Reactor Experiment for Neutrino Oscillation) has obtained a more precise value of the smallest mixing angle θ_1_3 and the first result on neutrino squared-mass difference |Δm"2_e_e| from an energy- and baseline-dependent disappearance of reactor electron antineutrinos (ν_e) using 500 days of data. Based on the ratio of inverse-beta-decay (IBD) prompt spectra measured between two identical far and near detectors, we obtain sin"2 2θ_1_3 = 0.082±0.009(stat.)±0.006(syst.) and |Δm"2_e_e| = [2.62"+"0"."2"1_−_0_._2_3(stat.)"+"0"."1"2_−_0_._1_3(syst.)] × 10"−"3 eV"2. An excess of reactor antineutrinos near 5MeV is observed in the measured prompt spectrum with respect to the most commonly used models. The excess is found to be consistent with coming from reactors. A future reactor experiment of RENO-50 is proposed to determine the neutrino mass hierarchy and to make highly precise measurements of θ_1_2, Δm"2_2_1, and |Δm"2_e_e|.
[en] The LHCb experiment offers a complementary phase space region to ATLAS and CMS to study electroweak processes, thanks to the precision in the forward acceptance, corresponding to the pseudo-rapidity range 2 < η < 5. Here the measurement of the leptons asymmetry in the decay Z → μ"+μ"−, performed using data collected by LHCb during the LHC Run I data taking, is presented. By studying this asymmetry LHCb determined the effective electroweak mixing angle, with the highest precision of the LHC experiments.
[en] A survey is presented of results from some recent searches for new physics in final states with jets or vector bosons such as dijet, black holes, massive resonances or vector-like quarks searches. The results are based on 13TeV or 8TeV proton-proton collisions data collected by the CMS detector at the LHC.
[en] The use of substructure in the ATLAS experiment has matured during the Run 1 analysis period into the most powerful new tool for understanding high-pT physics at the LHC. In this document we present the studies that have been instrumental in reaching that maturity for boosted hadronic W/Z, Higgs and top tagging. We also summarize the results from Run 1 and Run 2 searches for new physics using substructure, thus demonstrating the power of these new techniques.
[en] A high-performance thermonuclear plasma is a strong source of nuclear radiation, which includes neutron emission from the main fusion reactions and gamma-rays born from the interaction of supra-thermal ions and plasma impurities. Spectroscopic measurements of both types of radiation are an indirect probe of the distribution function of the fast ions leading to nuclear emission. In this paper we present a selection of recent results obtained with neutron and gamma-ray spectroscopy as a means to study the energy distribution of supra-thermal particles in high-performance thermonuclear plasmas. We focus in particular on the advancements made possible by the combination of dedicated instrumentation and detailed models based on the nuclear physics behind the emission. Future developments are finally addressed, especially regarding the availability of compact detectors with spectroscopy capabilities, which open up to a full tomographic reconstruction of the fast-ion velocity space.