Nuclear Physics at INFN Bari
In Italy, Nuclear Physics has a long and important tradition, thanks to the research on radioactivity of the Via Panisperna group in the 30s of the last century: the interest of scientists in this new field would soon lead to the discovery of various radioactive elements and finally of nuclear fission thanks to the technique of slow neutrons.
Today, research on core physics spans a wider range of energies: from the mechanisms that regulate the life of stars, to the conditions of the universe a few moments after the Big Bang. The mission to explore the physics of the nucleus is now interpreted in a very broad sense, including e.g., studies of the difference between matter and antimatter, the distribution of quarks within nucleons or the study of the nucleus as a complex multibody system at the mesoscopic scale. In the INFN, scientific research in this area is coordinated by the National Scientific Commission 3, and locally by Group 3.
The INFN division in Bari participates in the following research activities in this field:
ALICE A Large Ion Collider Experiment
The ALICE experiment aims to study the effects of interactions between heavy nuclei accelerated at high energies with CERN’s Large Hadron Collider (LHC).
The extreme conditions of the impact recreate those of the Universe shortly after the Big Bang, when the constituents of matter, quarks and gluons, were free and not confined within protons and neutrons as today.
The study of this phase of the evolution of the Universe will help us to understand the processes by which the particles that we observe today in nature and in particle accelerators are formed.
Local coordinator: Mastroserio Annalisa
JLAB12 Jefferson Lab
It includes all INFN experiments at Jefferson Lab, located in Newport News, Virginia, USA and dedicated to the study of hadron physics by means of an electron beam of high intensity and energy up to 12 GeV.
The experiments investigate the internal dynamics and structure of protons, neutrons and nuclei through the scattering of polarized electrons.
The Bari Group is involved in the study of nucleon form factors and the interaction of hadrons in (hyper)nuclei.
Local coordinator: Perrino Roberto
LUNA Laboratory for Underground Nuclear Astrophysics
the main goal of the LUNA experiment is the study of the nuclear reactions fundamental for stellar evolution.
These reactions have a dual function: they generate most of the energy produced by stars and allow the synthesis of almost all elements existing in nature. Since the reactions sought are very rare and are difficult to measure in surface laboratory, LUNA is located at the Laboratori Nazionali del Gran Sasso (L’Aquila), below the namesake mountain that, with its 1400 m of rock, guarantees the so called “cosmic silence”.
Local coordinator: Ciani Giovanni Francesco
The n_TOF experiment concerns the study of neutron-induced reactions of interest for Nuclear Astrophysics and Applications. In particular, the experimental activity is focused on the reactions underlying the production of elements in the Universe (stellar and Big Bang nucleosynthesis) as well as, in the application field, on measures relevant for the production of energy in fission and fusion reactors, for medical physics and neutron imaging.
The project takes place at the time of flight facility n_TOF (from “neutron Time-of-Flight) at CERN in Geneva. The neutron beam is produced by spallation from a primary beam of protons from 20 GeV/c of the PS (proto-synchrotron), on a lead target. The measurements are carried out in three experimental areas, located at different distances from the spallation source: EAR1, at 200 m and horizontal beam line, EAR2, at 20 m on the vertical, and NEAR, at 1.5 m. Each area is equipped with numerous detectors of various types, scintillation, solid state and gas. These include a 4p calorimeter for measuring neutron capture reactions (a detail is shown in the figure).
More than 120 researchers from 40 universities and research institutions, mostly European, are participating in the project. The Italian participation consists of several INFN Universities and Sections (Bari, Bologna, Catania, National Laboratories of Legnaro, Frascati and the South, Perugia, Rome, Turin and Trieste).
Local coordinator: Giuseppe Tagliente
The EIC_NET experimental initiative brings together the Italian community of researchers participating in the ambitious international project of the Electron Ion Collider (EIC) which aims to create an electron-ion collider, with the aim of systematically studying the many problems that still prevent a complete understanding of the nuclear force. These problems have not yet been explained by the theory of Quantum Chromo Dynamics (QCD), which describes the interaction between quarks, and consequently that between nucleons (protons and neutrons) composed by them.
Among the issues that the EIC project will address are: the contribution of quarks and gluons to the properties of nucleons, such as their mass, spin and radius, the density of gluons in nuclei and its possible saturation, which would create a kind of new form of matter, and the formation of hadrons from quarks and gluons in nuclear matter (a process that goes by the name of hadronization). To answer these questions and other questions of nuclear physics, we will investigate the diffusion processes between polarized electrons and ions (from hydrogen to lead, with the lightest polarized) with energies of the center of mass varying between 40 and 120 GeV, and produced by very intense beams.
The EIC_NET team participated in 2021 in the “Call for Collaboration Proposals for Detectors at the EIC“, contributing significantly to the formation of the proto-Collaboration ATHENA (A Totally Hermetic ElectronNucleus Apparatus) and the related proposal document for a “general purpose” detector at the IP6 main measuring point with a 3 T solenoid magnet.
Local coordinator: Domenico Elia