Nuclear physics in Italy
The Legnaro Laboratories
The study of the properties of highly unstable nuclei can yield
information vital to the verification of models of nuclear structure,
and can better our understanding of the reactions leading to
nucleosynthesis in stellar interiors.
In order to understand the limits of nuclear stability better,
nuclei can be subjected to extreme perturbations, as a result
of which they are left in conditions very different from those
in which they are found in ordinary matter. At the Legnaro Laboratories,
these conditions are created in collisions produced by the Tandem
and ALPI accelerators. The energy acquired at impact is released
by the nuclei in the form of gamma radiation, which, once detected,
provides information about nuclear stability. The measurement
of this radiation is performed using specifically designed detectors,
such as GASP and PRISMA.
The Laboratories are also home to the ultracryogenic antenna
AURIGA, which is dedicated to the search for gravitational waves
produced by violent astrophysical phenomena. AURIGA observations
are correlated with those from the NAUTILUS antenna at Frascati.
Moreover, the Legnaro Laboratories have a long tradition in
the application of accelerators and nuclear technology to interdisciplinary
activities in fields such as radiobiology, microdosimetry, materials
science, and the study of environmental pollutants. Specialized
laboratories and instrumentation have been created for these
purposes.
The Laboratories participate in initiatives organized at the
European level (the TRASCO and EURISOL projects) for the development
and construction of high-intensity proton accelerators to be
used for the transmutation of radioactive waste, the production
of high-flux neutron and neutrino sources, and the production
of beams of exotic nuclei at next-generation facilities.
The Southern Laboratories
Experiments underway at the Southern Laboratories are mainly
dedicated to fundamental nuclear physics, and make use of the
Tandem accelerator, in operation since the early 1980’s,
and the Superconducting Cyclotron (CS), in which devices with
operating temperatures of about
-269 °C are used. In current research, the structure of
exotic nuclei is being studied. Exotic nuclei are composed of
more protons or neutrons than normal. In collisions in which
the interaction energy takes on particular values, they are
heated and compressed and reach densities twice those of normal
nuclear matter. Afterwards, the nuclear matter cools and expands,
and breaks up into fragments.
The Laboratories have several different detectors available
for the analysis of the products of such interactions, including
the CHIMERA system, which consists of about 700 detectors installed
inside the CICLOPE vacuum chamber. This type of research is
aimed at obtaining a deeper understanding of important aspects
of astrophysics, for which the study of nuclear systems is fundamental.
A wide range of processes are of interest, from nucleosynthesis—the
formation of nuclei in the aftermath of the Big Bang—to
processes which take place in the interiors of neutron stars.
The Laboratories are participating in the construction of NEMO
(the Neutrino Mediterranean Observatory), an undersea telescope
for the observation of cosmic neutrinos. There are many unanswered
questions concerning the origin and nature of these particles.
In collaboration with the government agencies responsible for
public health and artistic preservation, the Laboratories have
developed applications of nuclear technology for useful social
purposes. Examples of such applications include a therapy for
ocular melanoma (developed by the CATANA group), and non-destructive
techniques for the analysis of historical and archeological
artifacts and the determination of their compositions (the LANDIS
laboratory). In addition to archeological artifacts, a painting
by Botticelli and a manuscript by Petrarch have been studied
using these techniques.
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