Calendario Dottorato

Ph.D in Physics

Journal Club Seminari 2023

08/11/2023  
aula F

ore: 15:00	Pietro Meloni DOTTORATO IN FISICA	The CYGNO Experiment: A Directional Detector with Optical Readout for Dark Matter Search
		The CYGNO project aims to prove the feasibility of utilizing a gaseous Time Projection Chamber (TPC) with optical readout to investigate Dark Matter (DM) in the low-mass range (1 GeV/c$^2$). A key feature of the CYGNO project is the ability to determine the direction of the recoiling nuclei, which is of great importance in DM search. The proposed detector includes a TPC chamber filled with a mixture of He:CF$_4$ at ambient pressure and temperature. The directionality of nuclear recoils can be determined by analyzing the distribution of primary electrons generated by the ionizing nucleus. Primary electrons are amplified using a triple layer of Gas Electron Multipliers (GEMs), and the resulting photons are detected by an external sCMOS camera and four PMTs. The purpose of this presentation is to share the latest findings from the latest prototype, LIME, with a volume of 50 liters, currently at Laboratori Nazionali del Gran Sasso (LNGS). The focus will be on the comparisons between experimental data and simulations, as well as the next steps for the LIME prototype

ore: 15:30	Laura Salutari DOTTORATO IN FISICA	Dark photon and dark Higgs at the Belle II experiment
		Abstract: Many questions remain open in the Standard Model of particle physics, and nowdays physicists seek for the answers with a wide range of experiments. Among all the collaborations, Belle II, a B-factory located in Japan, also has in its program to search for Beyond SM physics. In particular, it has an on going search for Dark Matter particles. The study project presented here is based on the simultaneous production of a dark photon A’ and dark higgs like boson h’, predicted in a variety of dark sector models, at the Belle II experiment. The research focus on the channel e^+ e^-→(A^'→μ^+ μ^- )h' with a center of mass energy       s=(10.58GeV)^2. This channel offers at least three different studies, covering a great deal of the still available parameter space of the theoretical models. One project is the update of a previous study published in 2022, in which the h’ is considered an invisible long lived particle and a luminosity l=8.34fb^(-1). The update will consist in using the lates available luminosity of l=427fb^(-1), which could lead to a significative improvement of the previous results on the cross section sensitivity of the experiment. Another project is to expand the research including the so called visible h’ hypothesis: to consider also an h’ decaying into SM particles, so a channel such as e^+ e^-→(A^'→μ^+ μ^- )  (h^'→l^+ l^- ). This project in fact can be further subdivided in two studies. One is to consider an h’ sufficiently long lived so that its decay particles have a displaced vertex with respect the IP;  one in which instead the lifetime is short and the h’ decays prompt, leaving no sign of displaced vertex. In the talk I will present the proper background in order to understand the three new scenarios and explain the setup work done up to now for these three different projects. ----

ore: 16:00	Elia Stanescu Farilla DOTTORATO IN FISICA	Study of the reactor electron antineutrino energy spectrum for the search of light sterile neutrino at the TAO experiment
		Neutrino oscillations have been measured with high accuracy in solar, atmospheric and long-baseline neutrino oscillation experiments. Several anomalies recorded in short-baseline neutrino experiments suggest the possibility that the standard 3-flavour framework may be incomplete and point towards a manifestation of new physics. Light sterile neutrinos provide a credible solution to these puzzling results.  The Taishan Antineutrino Observatory (TAO) is a state-of-the-art ton-level liquid scintillator detector, satellite experiment of the Jiangmen Underground Neutrino Observatory (JUNO) experiment, that will start by the end of 2024. Thanks to the record energy resolution of 1% at 1 MeV that aims to reach, TAO will provide an extremely accurate measurement of the reactor electron antineutrino energy spectrum. Simulations of the spectrum will be realized in the 3-flavour and 3+1 light sterile neutrino-flavour frameworks, with the aim to reproduce the anomalies showed by the previous short-baseline neutrino oscillation experiments.