Tag Archives: Evento scientifico

In this seminar, I will discuss the applications of linear and non-linear stochastic Schroedinger equations in quantum foundations as well as in the study of transport phenomena in open quantum systems. In quantum foundations, non-linear stochastic Schroedinger equations play a fundamental role in collapse models. In these models, the wavefunction collapse in space is described by a non-linear interaction with an external classical noise, resolving the measurement problem. From a mathematical point of view, the evolution of the state of the system is described by a class of non-linear stochastic Schroedinger equations, which will be discussed. Transport phenomena in open quantum systems are relevant in a large class of interesting systems. The study of the dynamics of a chain of harmonic oscillators locally connected to baths at an arbitrary temperature will be discussed. The advantages of solving the system dynamics using stochastic unravellings instead of working directly with the master equation will be highlighted. The study is relevant in the field of quantum thermodynamics as well as for exciton transfer in biological networks.

Recent progress in solid-state cavity-QED with semiconductor quantum dots enables efficient photonic quantum gates. Apart from studies of fundamentally new cavity QED effects, those systems allow the generation of high-brightness quantum light in Fock space at a strongly reduced experimental complexity. This opens up, for instance, a new kind of “quantum-light spectroscopy” that was not possible before, with applications and in order to address open questions in bio-molecular spectroscopy and microscopy. At the same time, the quantum dot cavity-QED systems can be used to create large entangled states involving potentially several tens of photons in a deterministic way, avoiding post-selection and therefore much more efficient exploration of those highly entangled systems, cluster and graph states, first steps in this direction will be shown.

Overview Image taken from http://discovermagazine.com/2014/dec/17-this-quantum-life   The main aim of the “New Quantum Horizons: From Foundations To Biology” Symposium is to discuss in an informal and friendly environment theoretical and experimental issues related to quantum physics, from foundational issues (such as connection between gravity and quantum physics, collapse models, spin-statistics) to applicative aspects, including new findings and ideas to investigate quantum effects in biological systems. The Symposium is supported by the Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Roma and by LNF-INFN. Conference Organizer: Catalina Curceanu, Laboratori Nazionali di Frascati, INFN, Italy Beatrix Hiesmayr, University of Vienna, Vienna, Austria Local Organizing Committee: A. Scordo, Laboratori Nazionali di Frascati, INFN, Italy A. Tamborrino Orsini, Laboratori Nazionali di Frascati, INFN, Italy

WIMPs mostly interacting with the SM states through a pseudoscalar mediator can achieve the correct relic density evading current constraints from Dark Matter Direct Detection. I will discuss some realistic implementation for a dark pseudoscalar portal with particular focus to the prospects for Direct Detection at next future facilities.

The aim of this talk is to review several aspects of two-gamma physics in relation to the exclusive process gamma gamma -> pseudoscalar meson, described by a transition form factor, as a function of the squared transfer momenta of the two photons. On this basis, the motivation for this kind of research, as well as its current status from theoretical and experimental points of view, will be discussed, e.g., recent BaBar measurements of the double off-shell photon transitions to eta’ mesons.

The presentation will begin with a brief overview of the research activity carried out at the Horia-Hulubei National Institute for Physics and Nuclear Engineering (IFIN-HH), Bucharest, Romania The seminar topic will focus mainly on the processes occurring in the rapid collisions of heavy-light ions such as 12C, 16O, 32S and 35Cl with thin (self-supporting) solid targets. The ionization and X-ray (characteristic and radiative electron capture-REC) cross sections from integral measurements of K and L X-ray yields have been determined. The measurements were performed at 9 MV FN Pelletron Tandem Accelerator of IFIN-HH. The measured X-ray cross-sections are useful in developing and testing theoretical models (such as PWBA + ECPSSR, SCA, geometric model, Stobbe formula for REC) and complements the existing database for atomic ionization cross-sections. They can have an important role in applied physics, such as elemental PIXE (Particle Induced X-ray Emission) analysis with heavy ions, heavier than proton. Within the last section of the seminar, I will discuss the PIXE method, along with other IBA techniques, which are used to characterize different type of materials. Thus, PIXE along with PIGE (particle-induced gamma-ray emission) and RBS (Rutherford backscattering spectrometry), are one of the "Total IBA" techniques, simultaneously applied in order to determine elemental concentrations and depth profiling of the thin films and various biological samples, with applications in materials physics and medicine. Certain measurements, on certain samples (such as antlers) have been obtained for the first time through the “total IBA”-type method, using the 3 MV Tandetron Accelerator of IFIN-HH, …

Motivated by an anomaly observed in the decay of an excited state of Beryllium by the Atomki collaboration, we study an extension for the Standard Model with a gauged U(1)’ symmetry. We show that this scenario complies with a variety of experimental results and is able to explain the potential presence of a resonant spin-1 gauge boson, Z’, with a mass of 17 MeV in the Atomki experimental data, for appropriate choices of U(1)’ charges and Yukawa interactions.

Axions and axion-like particles are excellent dark matter candidates, spanning a vast range of mass scales from the milli- and micro-eV for the QCD axion, to 1E-22 eV for ultralight axions in string theory. In some scenarios, inhomogeneities in the axion density lead to the formation of compact structures known as axion “miniclusters” and axion stars. I will first discuss astrophysical and cosmological constraints on axions at either end of this spectrum, using data from the cosmic microwave background anisotropies and the effects of miniclusters on the gravitational microlensing and on direct detection. I will then assess the formation and the evolution of axion stars in various astrophysical regimes.

The combination of precision space and time information in particle tracking has the capability of transforming how we design experiments, 4D tracking is being considered in the upgrade of the ATLAS, CMS and LHCb experiments at the High-Luminosity LHC, set to start data taking in 2024-25. Regardless of the type of solution chosen, space-time tracking brings benefits to the performance of the detectors by reducing the background and sharpening the resolution; it improves tracking performances and simplifies tracks combinatorics. Space-time tracking also allows investigating new physics channels, for example, it opens up the possibilities of new searches in long-living particles by measuring accurately the time of flight between the production and the decaying vertexes.