Categoria: News

Lettera del presidente INFN:

https://www.ticketone.it/eventseries/70-anni-di-conoscenza-delluniverso-2991797/

Mercoledì  22 settembre  2021

ore 15:00 

Marco Pallavicini

(Università di Genova)

 terrà un seminario dal titolo

 “ Seeking the true nature of neutrinos: was Ettore Majorana right ? ”

abstract:

After almost 100 years since its birth, the neutrino is still the less understood particle of the Standard Model, the established theory of particles and fields. Neutrinos are the most abundant massive particles of the universe (as far as we know) and they are emitted copiously by stars, nuclear reactor, particle accelerators, the Earth and even the human body, but despite many recent discoveries they remain very mysterious on several aspects. The so called Neutrino-less Double Beta decay, a very rare radioactive decay of some nuclei, may, despite its name, offer the opportunity to uncover the main mystery about neutrinos, namely if they behave like the other spin ½ particles of the Standard Model or, uniquely, they behave as predicted by Ettore Majorana in the middle 30s, when the brilliant Italian theoretician developed a theory of neutrinos as possible alternative with that developed by Paul Dirac. While it is clear that charged particles must follow Dirac theory, the Majorana option is still perfectly valid for neutral particles such as neutrinos. The seminar will go through neutrino properties and history and finally describe how neutrino-less double beta decay may teach us if Ettore was right or wrong.

Il seminario si terrà in modalità telematica. Il link per collegarsi all’evento:

Abstract:

“Neutrino have never ceased to provide tantalizing questions and  experimental surprises, providing possibly the strongest hints of physics beyond the current Standard Model.
The Deep Underground Neutrino Experiment (DUNE) is an international experiment that will consist of two detectors exposed to the the most intense neutrino beam in the world. A “near” detector will record the interactions of neutrinos close to the source, at the Fermi National Accelerator Laboratory in Batavia, Illinois while the “far” detector, consisting of four large TPCs immersed in ~ 80000 t of liquid Argon, will be installed in the Sanford Underground Research Facility in Lead, South Dakota, 1,300 km away from the point of production and 1.5 km underground.

The DUNE experiment has a wide experimental program, whose main topics are:

neutrino oscillation physics: the main goal of the experiment is the determination of the neutrino mass ordering and the possible CP symmetry violation in the leptonic sector.  This might provide information on the origin of the matter-antimatter asymmetry, one of the fundamental questions in physics of particles and in cosmology.

proton decay: its observation would be a sensational discovery in particle physics and providing a key point for grand unification theories.

observation of neutrinos coming from the collapse of a supernova in our galaxy: the measurement of the neutrino flux coming from this source would provide unique information about the first stage of the nucleus collapse and on the formation of a neutron star. DUNE could also allow  for the observation of the formation of a black hole.

Moreover, in consideration of the large statistics, it will provide the most comprehensive set of measurements of neutrino induced reactions and will be sensitive to several signatures of physics beyond the Standard Model.”

Abstract e slide disponibili su: https://agenda.infn.it/event/27731/

Il seminario si terrà via Zoom al seguene indirizzo:

https://infn-it.zoom.us/j/84261721878?pwd=MDZNaGdBUlcvUUJXa2phSHZVZk5sdz09

ID riunione: 842 6172 1878
Passcode: 611379

Abstract:

A puzzling anomaly has been recently observed in the emission of electron-positron pairs in the 7Li(p,e+e-)8Be and 3H(p, e+e-)4He reactions. This anomaly has been interpreted as the signature of a
new boson particle, not foreseen in the Standard Model, with mass 16.8 MeV (hereafter called the X17 boson). Various theoretical speculations have been advanced, as for example that the X17 boson could be either a mediator of a fifth force, characterized by a strong coupling suppression of protons compared to neutrons, or a “piophobic” axion-like-particle. The fifth force scenario can explain, at least partially, the long standing anomaly of the magnetic moment of muon found experimentally. In order to test these assumptions, it is important to properly treat the nuclear dynamics. In this talk, we present the results of a theoretical study of the 3H(p, e+e-)4He and 3He(n, e+e-)4He reactions, and discuss how the different scenarios agree with the available experimental data. We will also briefly discuss about the present and future experimental activities stimulated to either confirm or reject this anomaly.

https://agenda.infn.it/event/27625/

Abstract: 
SWEATERS is a project, at INFN Pisa, devoted to the development of new instrument as energetic neutral atoms (ENA) detector for Space Weather Program to be built with an innovative technology. The energy range of interest is from few keV to 100 keV. Our device 
is a sort of a "gas calorimeter for ENA particles" with high spatial resolution based on Micro-Pattern Gas Detector (MPGD) technique with the possibility to provide a 3D track reconstruction. The innovative design of our instrument is based on a well consolidated experience on gas detectors for high energy physics with the intent to move this technology within the scientific field of ENA particles. 
The ENA, indeed, are low energy particles generated by the charge-exchange process, any time the solar wind plasma ions interact with neutral atoms forming the background gas present in the magnetosphere of the Earth. Their study is of great interest to provide fundamental information about Solar wind interaction with Earth and Planetary environments. 

In this talk, I am going to present the scientific activity of the project, the current status and the future perspectives of the SWEATERS project as a test facility of gas detectors for low energy ionizing particles operated at low pressure.

Trovate la connessione  Zoom  in questa pagina Indico https://agenda.infn.it/category/1515/

Abstract:

The TOTEM experiment at LHC has performed total and differential elastic p-p cross-section measurements at different LHC energies. Since 2018 a first hint of the presence of the Odderon was found in TOTEM results. Now the discovery has been confirmed after a comparison with the p-bar-p data measured by the D0 collaboration at Fermilab.

The comparison of the two experiment results led to the first experimental observation of the exchange of the Odderon with a significance of 5.4σ.

The Odderon, first theorized in 1973, represents the C-odd counterpart of the Pomeron, the dominant Regge trajectory in the soft high energy diffractive interactions.

The Odderon emerges not only in the Regge framework, but also in QCD theory where it can be modelled as an exchange of a colourless C-odd gluonic compound.

States comprising two, three or more gluons are usually called “glueballs”, and their observation represents a key test of the QCD.

The talk will give a theoretical introduction to the Odderon in the context of both Regge and QCD frameworks, highlighting the best strategy to observe such enigmatic object at the LHC.

The TOTEM experiment and results will be described and a detailed report of the latest analysis, in collaboration with D0, will be given. The future measurements of TOTEM at a centre-of-mass energy of 14 TeV will be briefly commented as well.

L’INFN ha assegnato i premi annuali per le migliori tesi di dottorato nelle cinque aree di ricerca dell’Istituto, ovvero in fisica subnucleare, astroparticellare, nucleare, teorica e tecnologica, e su attività di ricercae sviluppo nell’ambito del calcolo. I premi, del valore di 2.000 euro ciascuno e assegnati dalle cinque Commissioni Scientifiche Nazionali (CSN) e dalla Commissione Calcolo e Reti (CCR) dell’INFN, sono intitolati alla memoria di illustri fisici italiani o colleghi dell’INFN: Marcello Conversi, Bruno Rossi, Claudio Villi, Sergio Fubini, Francesco Resmini e Giulia Vita Finzi.