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Science highlights of the Fermi-LAT
Get PDFThe LAT (Large Area Telescope) experiment is a gamma-ray detec- tor onboard the Fermi satellite, sensitive to energies from 20 MeV to over 300 GeV. Launched in 2008, the main goal of the experiment is to study the origin and nature of high-energy gamma rays in the universe through the search for particle accelera- tion mechanisms and electromagnetic radiation emission from sources such as active galactic nuclei (AGN), pulsars, and supernova remnants, the study of galactic and extra-galactic diffuse gamma ray emission, the search for unidentified gamma-ray sources, the indirect detection of dark matter through its decay or annihilation into photons as the final state, and the study of high-energy emission from transient sources such as solar flares and gamma-ray bursts (GRBs). This contribution will illustrate the main scientific results obtained by the experiment in recent years
Light (anti)nuclei production with the ALICE experiment at the LHC
Get PDFThe measurement of light (anti)nuclei production in high-energy pp, p–A, and A–A collisions is a powerful tool to understand the hadronization process. The ALICE experiment, among the LHC experiments, is particularly well suited for the study of light (anti)nuclei production thanks to its excellent tracking capabilities and particle identification in a wide range of transverse momentum. Particles with mass numbers up to A=4, such as (anti)deuterons, (anti)tritons, (anti)3He, and (anti)4He have been successfully identified in the pseudorapidity region |η| < 0.9. In this contribution selected results on light (anti)nuclei production are presented, such as particle yields, transverse momentum distribution and comparison with hadronization models. In addition recent results on (anti)deuteron production in jets are discussed
Probing the tau lepton magnetic moment at future lepton colliders
Get PDFThe anomalous magnetic moments of leptons are excellent candidates not only to test the Standard Model predictions, but also to investigate possible new physics effects. The long-standing discrepancy between the Standard Model prediction and the experimental measure of the muon g − 2 motivates the study of non-standard effects also in the electron and tau g − 2. In our work, we show the potential sensitivity of future lepton colliders (FCC-ee or a high-energy Muon Collider) to probe the tau g − 2. We point out that these facilities can generate processes like the radiative Higgs decay h —> T+T- Y or the Drell-Yan processes l+l- —> T+T- (h) enabling to test the tau g − 2 with a resolution of O (10-5 - 10-4) that is orders of magnitude better than the current LEP sensitivity
The DAMPE space mission
Get PDFThe DArk Matter Particle Explorer (DAMPE) is a satellite-based cosmic-ray experiment that has been operational for almost 8 years. Since its launch in December 2015, it is continuously collecting data on high-energy cosmic particles with very good statistics and particle identification capabilities, thanks to a large geometric factor and a good energy resolution. In this contribution some of the latest results are presented and discussed
Politiche a sostegno dell’automotive che cambia
Get PDFLa ricerca di nuovi metodi di propulsione per le automobili è oggetto di intenso dibattito a tutti i livelli a causa del riscaldamento globale, delle emissioni degli agenti inquinanti e più in generale per la necessità di proteggere in modo sostenibile l’industria automobilistica dai paesi produttori di nuova industrializzazione. Le trasformazioni in corso dell’ecosistema automotive per potersi tramutare in opportunità per l’intera filiera produttiva italiana, e non tramutarsi in occasioni mancate, necessitano inevitabilmente del supporto e dell’indirizzamento delle istituzioni e in particolare del Governo centrale. In particolare, il ruolo dell’automobile come elemento di mobilità è in fase di rinegoziazione e implica, in primo luogo, decisioni di natura pubblica in termini essenzialmente di regolamentazione, incentivazione e tassazione, con inevitabili conseguenze sui modelli di sviluppo delle imprese appartenenti alla filiera automobilistica e a quei territori altamente specializzati in tali attività. Nei paesi con un’importante tradizione automobilistica, gli interventi di politica industriale a livello nazionale e regionale sono stati significativi e di varia natura fino alla presenza diretta degli stati nel capitale sociale degli assemblatori finali e dei fornitori, come è avvenuto in Francia e in Germania. Difendere la produzione italiana nell’assemblaggio finale come nella fornitura significa
salvaguardare, oltre a un comparto industriale strategico, una considerevole porzione di PIL e l’occupazione di quasi un milione di addetti
Characterization of ultra radiation hard pixel detectors for the high luminosity phase of the CMS experiment at the LHC
Get PDFThe High Luminosity upgrade of the CERN Large Hadron Collider (HL-LHC) calls for new radiation tolerant silicon pixel sensors. In the case of the CMS experiment, the innermost tracker layers will have to withstand an integrated f luence up to 2.3×1016 neq/cm2 (1 MeV equivalent neutrons) while preserving high tracking efficiency. In order to maintain or even improve the performance of the CMS
inner tracker in this harsh environment an extensive R&D program has been put in place by the CMS collaboration targeting thin planar and 3D pixel sensors. The basic cell size of the module has an area of 25×100 μm2 and an active thickness of 150 μm. The modules are read out by the CMS Read Out Chips (CROC) built in 65 nm technology and developed by CMS and ATLAS Collaborations within the RD53
Collaboration. This contribution describes test beam results of the new 3D and planar sensor prototypes read out by a single chip, both before and after irradiation and of the first planar quad sensor, i.e., read out by four chips, before irradiation. The modules performance were evaluated in terms of hit detection efficiency and resolution. The analysis of collected data shows excellent performance even for the irradiated modules
Toward a theory of neutrino mass and mixing
Get PDFAmong numerous theoretical ideas, approaches, mechanisms,
models there are probably few elements which will eventually enter the true theory of neutrino masses and mixing. The task is to identify them. Still something conceptually important can be missed. The problems of construction of the theory are
outlined. Perspectives and possible future developments are discussed
Statistical analysis of Core-Collapse explosion parameters: An astrophysical probe for Supernova neutrino flux
Get PDFCore-Collapse (CC) Supernovae (SNe) are among the most extreme and luminous astrophysical phenomena, besides sites of intense neutrino production and particle acceleration. The electromagnetic observations of these transients allow
us to characterize the explosion energy and the configuration of the progenitor star at the explosion time. This information provides an important constraint in the SN
neutrino flux in terms of energy, flavor, and intensity. The launch of the Legacy Survey of Space and Time and other future dedicated optical surveys are going to open the possibility to perform statistical studies on the CC SNe parameters. These studies need sufficiently fast and accurate procedures for the characterization of SN events. In this framework, we have developed semi-/analytical models and Bayesian modeling procedures, which reconstruct SN Light Curves and infer the main explosion parameters connecting them with the expected neutrino spectrum
Gamow-Teller decays: Probing nuclear structure and weak interactions
Get PDFWe describe the Gamow-Teller decays for nuclear systems outside the 40Ca and 56Ni closed cores in the framework of the realistic shell model, starting from a nuclear Hamiltonian and electroweak currents as consistently obtained by means of chiral perturbation theory. The effective shell-model Hamiltonians and decay operators are derived using many-body perturbation theory, allowing the role of both electroweak currents and many-body correlations to be taken into account as the origin of the problem of the quenching of the axial coupling constant gA