Seminários do DRCC

Abstract: A minimal model is presented with gauged Baryon number, Dirac neutrino masses, and a dark sector in which the dark matter plays the leading role in creating a CP asymmetry that is the source of the baryon asymmetry of the Universe.

End of  Second Semester of 2021

Abstract: Fusion energy offers the potential for safe, abundant, and reliable energy to support a sustainable global energy system in the latter half of this century. The landscape of fusion research is advancing rapidly, with major public and private investment in fusion technologies and power plant development programmes. Nevertheless, the physics and engineering of fusion remain extremely challenging – particularly regarding the confinement and safe exhaust of hot fusion plasmas. This talk will overview recent developments in this area around the world, and outline some of the exciting work in the years to come”

Abstract: I review a range of anomalous phenomena with macroscopic consequences in various relativistic forms of matter. The corresponding phenomena came prominently to light only in the last decade in the realm of nuclear physics. Among the most interesting of them are the anomalous phenomena driven by the chiral magnetic, chiral separation, and chiral vortical effects. They can lead to observable signatures in heavy-ion collisions, stellar astrophysics, cosmology, and even in Dirac and Weyl semimetals

Abstract:  The observation of gravitational waves from a blackhole-mystery object binary opens the possibility for heavy neutron stars of 2.5 solar masses (potentially seen in GW190814). If this mystery object is a neutron star of 2.5 solar masses, it poses direct challenges to models of the equation of state. Interestingly, introducing non-trivial structure in the speed of sound sourced by changes in the degrees of freedom (possibly quarks) of ultra-dense matter can resolve this conflict, which may have large ramifications in nuclear and astrophysics. However, for a clear smoking gun signature of the mystery object being a neutron star, one requires a measure of tidal deformability that is non-zero. Because the predicted values are very small, a tenfold increase in sensitivity may be needed to test this possibility with gravitational waves, which is feasible with third generation detectors.”

Abstract:  The study of QCD matter in extreme conditions of temperature and density such as those existing shortly after the Big Bang or in the core of neutron stars brings many insights into the innermost structure of the matter and the forces between its building blocks. While gravitational wave events revealed a glimpse of QCD matter at extreme conditions, the future Facility for Antiproton and Ion Research (FAIR) will directly create and investigate its properties in the laboratory. Nucleus-nucleus collisions at SIS100 beam energies produce very high net-baryon densities, where phenomena such as a first-order phase transition between hadronic and partonic matter or even exotic phases, are expected. The Compressed Baryonic Matter (CBM) is a dedicated heavy-ion experiment designed to explicitly access rare observables sensitive to the medium. For high-statistics measurements of rare probes, event rates of up to 10 MHz are needed. To meet these demands, the CBM experiment uses fast and radiation hard detectors, self-triggered detector front-ends, and a free-streaming readout architecture. Several of the CBM detector systems, the data read-out chain, and event reconstruction are commissioned and already used in experiments during the FAIR phase 0, and also within a full-system setup at GSI SIS18. In this presentation, the physics program of CBM will be reviewed and the current status of the experiment will be reported.

Abstract: We are experimentally investigating possible departures from the standard quantum mechanics predictions at the Gran Sasso underground laboratory in Italy. In particular, with advanced radiation detectors, we are searching for signals coming from a possible violation of the Pauli Exclusion Principle, motivated by quantum gravity models, and we test, with unprecedented sensitivity, collapse models which were proposed to solve the“measurement problem” in quantum physics. In my talk,  I shall present the most recent results we obtained in testing the Pauli ExclusionPrinciple [1] by searching for “impossible” atomic transitions and in testing various types of collapse models by searching the spontaneous emission of radiation, predicted by these models. In particular, I shall discuss our recent results, published in Nature Physics [2] under the title“Underground test of gravity-related wave function collapse”, where we ruled out the natural parameter-free version of the gravity-related model. I shall then present more generic results on testing CSL (Continuous Spontaneous Localization)collapse models and will conclude with future perspectives, both from experimental and theoretical points of view.

Abstract: Hadrons interact via a residual strong force that is unmeasured for most hadron species. The measurement and quantitative understanding of the strong interaction among hadrons are considered to be one of the frontiers within the standard model of nuclear and particle physics. Not only the interaction studies are important to understand the strong interaction in detail, but their knowledge has important implications for the equation of the state of neutron stars. The ALICE collaboration recently demonstrated that by combining excellent particle identification and a momentum correlation analysis method applied to pp and p–Pb collisions at the LHC, it is possible to measure the strong interaction among all hadrons containing strange quarks and protons. In this talk,  I will discuss the recent measurements carried out in this sector that allowed us to measure with unprecedented precision the following interactions: K^–p, p–Lambda, p–Sigma, p–Xi^–an p–Omega^–. The measured correlation functions can be used to test predictions from chiral effective field theory or lattice calculations for different channels and so far unknown features of the strong interaction will be discussed. The consequences for the physics of neutron stars will be presented. These measurements open a new avenue in nuclear physics, with the potential of accessing the strong force between any hadron pair.