The Laboratori Nazionali di Legnaro (Legnaro National Laboratories, LNL) is one of the four major research centers of the Italian
National Institute for Nuclear Physics (INFN).
The primary focus of research at this laboratory is in the fields of
nuclear physics
Nuclear physics is the field of physics that studies atomic nuclei and their constituents and interactions, in addition to the study of other forms of nuclear matter.
Nuclear physics should not be confused with atomic physics, which studies th ...
and
nuclear astrophysics
Nuclear astrophysics studies the origin of the chemical elements and isotopes, and the role of nuclear energy generation, in cosmic sources such as stars, supernovae, novae, and violent binary-star interactions.
It is an interdisciplinary part ...
, where five accelerators are currently used. It is one of the most important facilities in Italy for research in these fields.
The main future project of the laboratory is the Selective Production of Exotic Species (SPES), in which various
radionuclides
A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ...
will be produced for research and medicinal purposes.
History
The establishment of a laboratory in
Legnaro
Legnaro is a ''comune'' in the Province of Padua in the Italian region Veneto, located about southwest of Venice and about southeast of Padua. As of 31 December, 2010, it had a population of 8,594 and an area of .All demographics and other stati ...
was first suggested in 1956 to promote nuclear physics research in Italy, in addition to previous work in
particle physics
Particle physics or high-energy physics is the study of Elementary particle, fundamental particles and fundamental interaction, forces that constitute matter and radiation. The field also studies combinations of elementary particles up to the s ...
. In 1959, the
University of Padua
The University of Padua (, UNIPD) is an Italian public research university in Padua, Italy. It was founded in 1222 by a group of students and teachers from the University of Bologna, who previously settled in Vicenza; thus, it is the second-oldest ...
decided that a new laboratory would be built near Legnaro, rather than installing new equipment in older facilities. The laboratory was founded in 1960 by physicist
Antonio Rostagni and research commenced within the next year. After initial investigations demonstrated the conceived role of the Legnaro Laboratories in nuclear physics research, the facility became integrated into the INFN in 1968.
In subsequent years, several accelerators were newly installed or upgraded. The original CN accelerator, whose operations commenced with the opening of the laboratory, was upgraded to allow the use and study of heavier ions. More advanced facilities were installed in the next decades: the XTU Tandem accelerator in 1981 (inaugurated in 1982) and the Linear Superconducting Accelerator (ALPI) in 1991. The installation of new facilities enabled more advanced studies to be performed at the Legnaro laboratories, increasing their importance in international research in nuclear physics.
Currently, most work at the Legnaro National Laboratories involves studies of
nuclear structure
Understanding the structure of the atomic nucleus is one of the central challenges in nuclear physics.
Models The cluster model
The cluster model describes the nucleus as a molecule-like collection of proton-neutron groups (e.g., alpha particl ...
,
nuclear reaction
In nuclear physics and nuclear chemistry, a nuclear reaction is a process in which two atomic nucleus, nuclei, or a nucleus and an external subatomic particle, collide to produce one or more new nuclides. Thus, a nuclear reaction must cause a t ...
s, and
gamma-ray spectroscopy; the last was internationally recognized in the 1990s.
The recent focus of the Legnaro Laboratories, and the main future project, is SPES (Selective Production of Exotic Species).
A new accelerator for the production of
radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
ion beam
An ion beam is a beam of ions, a type of charged particle beam. Ion beams have many uses in electronics manufacturing (principally ion implantation) and other industries. There are many ion beam sources, some derived from the mercury vapor ...
s has been under construction since 2007,
and the alpha phase of the project, featuring a new cyclotron, was inaugurated in December 2016.
Subsequent beta, gamma, and delta phases are planned, approved, and funded by INFN and the Italian government; it will be possible to synthesize new isotopes and mass produce
medically useful isotopes once they are completed.
Facilities and projects
Accelerators
There are six accelerators in operation at the Legnaro National Laboratories:
* CN: installed in 1961. The maximum energy reached for beams was 7
MeV
In physics, an electronvolt (symbol eV), also written electron-volt and electron volt, is the measure of an amount of kinetic energy gained by a single electron accelerating through an electric potential difference of one volt in vacuum. When us ...
, but nowadays runs at 5.57 MeV energy. 7-meter-tall (vertically installed) electrostatic accelerator.
* AN 2000: installed in 1971, 2 MeV beams. Electrostatic accelerator.
* XTU-TANDEM (or TANDEM-XTU): inaugurated 1982. Beam energies up to a few hundred MeV. Electrostatic accelerator.
* ALPI (Acceleratore Lineare Per Ioni, Linear Superconducting Accelerator): Started operation in 1991. A superconducting cryogenic linear accelerator. Boosts beams from the TANDEM-XTU and PIAVE accelerators.
* PIAVE (Positive Ion Accelerator for Very Low velocity ions): Entered operation in late 2014. Superconducting linear accelerator used as an injector to ALPI. A few meters in length.
* P70 cyclotron: inaugurated 2 December 2016. Part of the SPES project.
All accelerators are used to accelerate various ions for nuclear physics purposes.
AURIGA

The Legnaro National Laboratories are the site of
AURIGA
Auriga is a constellation in the northern celestial hemisphere. It is one of the 88 modern constellations; it was among the 48 constellations listed by the 2nd-century astronomer Ptolemy. Its name is Latin for '(the) charioteer', associating i ...
, a
gravitational wave detector for astrophysical
gravitational waves
Gravitational waves are oscillations of the gravitational field that travel through space at the speed of light; they are generated by the relative motion of gravitating masses. They were proposed by Oliver Heaviside in 1893 and then later by H ...
research.
It became operational in 2004, and has been continuously in operation since then. In 2016, it was proven that the AURIGA
resonant mass detector is sufficiently sensitive for
dark matter
In astronomy, dark matter is an invisible and hypothetical form of matter that does not interact with light or other electromagnetic radiation. Dark matter is implied by gravity, gravitational effects that cannot be explained by general relat ...
searches, and perhaps more suitable than more modern detectors such as
LIGO
The Laser Interferometer Gravitational-Wave Observatory (LIGO) is a large-scale physics experiment and observatory designed to detect cosmic gravitational waves and to develop gravitational-wave observations as an astronomical tool. Prior to LIG ...
.
The experiment is closed and the AURIGA antenna is an exhibit at LNL (since April 2021).
SPES
The SPES (Selective Production of Exotic Species) project involves the construction of several new accelerators specially designed for the production of radioisotopes. In the beta phase,
fission at 10
13 fissions per second
and fragmentation of
uranium
Uranium is a chemical element; it has chemical symbol, symbol U and atomic number 92. It is a silvery-grey metal in the actinide series of the periodic table. A uranium atom has 92 protons and 92 electrons, of which 6 are valence electrons. Ura ...
will be studied to yield exotic neutron-rich
isotope
Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...
s and produce beams with these isotopes at higher intensities than those currently available. These include nuclei near the
nuclear drip line
The nuclear drip line is the boundary beyond which atomic nuclei are unbound with respect to the emission of a proton or neutron.
An arbitrary combination of protons and neutrons does not necessarily yield a stable atomic nucleus, nucleus. One ...
s and
shell closures that play an important role in the astrophysical
r-process
In nuclear astrophysics, the rapid neutron-capture process, also known as the ''r''-process, is a set of nuclear reactions that is responsible for nucleosynthesis, the creation of approximately half of the Atomic nucleus, atomic nuclei Heavy meta ...
.
A variety of medically useful radioisotopes will also be mass produced as part of the project's gamma phase.
By 2017, significant progress was made on the construction of the SPES facility; the first beams of exotic isotopes are expected to be available in late 2019.
[
]
Gamma-ray spectroscopy
Experiments using gamma-ray spectroscopy are underway at several European laboratories including the Legnaro National Laboratories. They address the structure of atomic nuclei, as well as their unbound states and roles in nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons (protons and neutrons) and nuclei. According to current theories, the first nuclei were formed a few minutes after the Big Bang, through nuclear reactions in ...
processes. At present, LNL delivers stable ion beams, but with the development of SPES high-intensity radioactive ion beams will also be available.
The major apparatus installed in the laboratories includes PRISMA (heavy ion magnetic spectrometer, with trajectory reconstruction system), GALILEO (Hyper pure Germanium gamma-ray detector system, that can be complemented by scintillator detectors) and EXOTIC (a device for light exotic beam production and study).
Since 2021, the travelling European AGATA
Advanced Gamma Tracking Array
spectrometer is installed at the Tandem-Alpi-Piave complex. It is currently coupled to the PRISMA magnetic spectrometer. In the future, thanks to the new beam interconnection between the Tandem-Alpi-Piave complex and the SPES project, the AGATA system will receive exotic beams produced by the SPES facility.
See also
* Laboratori Nazionali del Gran Sasso
Laboratori Nazionali del Gran Sasso (LNGS) is the largest underground research center in the world. Situated below Gran Sasso mountain in Italy, it is well known for particle physics research by the INFN. In addition to a surface portion of t ...
* Laboratori Nazionali di Frascati
The INFN National Laboratory of Frascati (LNF) was founded in 1954 with the objective of furthering particle physics research, and more specifically to host the 1.1 GeV electrosynchrotron, the first accelerator ever built in Italy. The La ...
References
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Physics laboratories
Research institutes in Italy
Laboratories in Italy
1960 establishments in Italy