The Legnaro National Laboratories and the SPES facility: nuclear structure and reactions today and tomorrow

Abstract

There is a very long tradition of studying nuclear structure and reactions at the Legnaro National Laboratories (LNL) of the Istituto Nazionale di Fisica Nucleare (Italian Institute of Nuclear Physics). The wide expertise acquired in building and running large germanium arrays has made the laboratories one of the most advanced research centers in γ-ray spectroscopy. The 'gamma group' has been deeply involved in all the national and international developments of the last 20 years and is currently one of the major contributors to the AGATA project, the first (together with its American counterpart GRETINA) γ-detector array based on γ-ray tracking. This line of research is expected to be strongly boosted by the coming into operation of the SPES radioactive ion beam project, currently under construction at LNL. In this report, written on the occasion of the 40th anniversary of the Nobel prize awarded to Aage Bohr, Ben R Mottelson and Leo Rainwater and particularly focused on the physics of nuclear structure, we intend to summarize the different lines ofresearch that have guided nuclear structure and reaction research at LNL in the last decades. The results achieved have paved the way for the present SPES facility, a new laboratoriesinfrastructure producing and accelerating radioactive ion beams of fission fragments and other isotopes. Keywords: nuclear physics, nuclear structure, nuclear reactions, heavy-ion accelerator, radioactive ion beam facility research infrastructure providing beam time and use of detectors to outside researchers. The research program is conducted by more then 500 scientists originating from several countries, technical staff and students. The main focus concerns research in nuclear physics, based on accelerated heavy-ion beams, and in applications using nuclear physics technologies. The laboratories is also involved in research in basic interactions, gravitational waves, accelerator physics, energetics, material science, biology, medicine and the effects of radiation on materials. It also contributes to numerous national and international projects hosted in other universities

Physics opportunities with the Advanced Gamma Tracking Array: AGATA

“…The latter constitute an almost unexplored territory, ideal for investigations with AGATA coupled to light charged-particle detectors, using intense stable beams. For example, reactions such as 6,7 Li on 6,7 Li, 9 Be, 10,11 B, and 12,13 C targets, will lead, after a single proton evaporation, to the population of unbound states in 13 B, 15 C, 17,19 O, and 16,17 N, respectively. Shape coexistence occurs when different microscopic configurations correspond to similar binding energies, as illustrated by the wave functions of 0 + states in the neutron-rich krypton isotopes beyond N = 60 (left), where oblate and prolate shapes are expected to coexist.…”

“…The Laboratori Nazionali di Legnaro (LNL) [17] provides heavy-ion beams from the 15 MV Tandem and from the ALPI superconducting LINAC, the latter either coupled to the Tandem or to the heavy-ion injector PIAVE. Stable beams range from protons to lead with energies up to 10-15 MeV/A.…”

“…They will be studied at LNL in an exotic region of the nuclear chart, following their evolution along isotopic chains. Pygmy states in stable systems have been investigated at LNL using inelastic scattering with 17 O heavy ions (at 20 MeV/A) [139] and the very first implementation of AGATA, coupled with segmented silicon detectors of the TRACE project [29]. A new mode of nuclear excitation, the Pygmy Quadrupole Resonance (PQR), associated with a concentration of low-energy electric quadrupole strength, was also observed [140].…”

“…AGATA is a truly universal high-resolution spectrometer, capable of measuring γ rays from a few tens of keV to beyond 10 MeV, with unprecedented efficiency, excellent position resolution for individual γ -ray interactions and correspondingly unparalleled angular resolution, and very high count-rate capability. These features will give rise to a resolving power that is in specific cases up to two orders of magnitude larger than current arrays, and allow AGATA to be operated in diverse environments such as using relativistic beams from the FAIR/Super-FRS facility [11,12], high-intensity ISOL beams from the secondgeneration Radioactive Ion Beam (RIB) facilities (HIE-ISOLDE [13], SPES [14], SPIRAL2 [15]), and at the highintensity stable beam facilities at GANIL [15], JYFL [16], and LNL [17].…”

Biomedical Research Programs at Present and Future High-Energy Particle Accelerators

“…Selective Production of Exotic Species (SPES) 13 is a second-generation ISOL facility on which the short- and long-term strategies of the laboratory are centered [ 74 ]. It is an interdisciplinary project, ranging over nuclear physics, nuclear medicine, and materials science.…”