Status of the SPES Exotic Beam Facility Comunian, M; Andrighetto, A; Antonini, P ...
Journal of physics. Conference series,
01/2020, Volume:
1401, Issue:
1
Journal Article
Peer reviewed
Open access
At Legnaro National Laboratories of INFN is under construction a Rare Isotope Facility called "Selective Production of Exotic Species" (SPES) based on a 35-70 MeV proton cyclotron, able to deliver ...two beams with a total current up to 0.75 mA, an ISOL fission target station and an existing ALPI superconducting accelerator as a post accelerator (up to 10 MeV/u for A/q=7). The paper will cover notably: the high-resolution mass separator, the CW RFQ (80 MHz, 727 keV/u, with internal bunching), the 1+ low energy transfer line and the injection line from Charge Breeder to ALPI under installation.
SPES (Selective Production of Exotic Species) is an ISOL type facility for production and post-acceleration of exotic nuclei for forefront research in nuclear physics. Radioactive (RA) species (A = ...80÷160) will be produced by fissions induced by a proton beam impinging on an UCx target: the proton beam will be delivered by a commercial cyclotron with a 40 MeV maximum energy and a 0.25 mA maximum current. The RA species, extracted from the Target-Ion-Source system as a 1+ beam, will be cooled in a RFQ (radiofrequency quadrupole) beam cooler (RFQ-BC) and purified from the isobars contaminants through a High Resolution Mass Separator (HRMS). Post-acceleration will be performed via an ECR-based charge breeder, delivering the obtained q+ RA beam to a being built CW RFQ and to the being upgraded superconducting (sc) linac ALPI (up to 10 MeV/A for a mass-to-charge ratio A/q = 7).
Proton energy calibration and identification efficiency of few Thallium activated Cesium Iodide (CsI(Tl)) crystals of the FAZIA detection system, have been studied in the range 59-180 MeV by using ...the proton beam delivered by the cyclotron of the CCB (Cyclotron Center Bronowice) facility. We observe that the light output versus energy is linear in the lower investigated energy range while showing a deviation from linearity above 140 MeV. The effects of proton induced nuclear reactions and multiple scattering causing incomplete energy deposition (IED) events have been identified and estimated via Pulse Shape Analysis in CsI(Tl) crystals. The measured experimental efficiency for proton identification in the examined energy range is then compared with GEANT4 simulations. For a centered collimated irradiation on the crystal, and at the highest measured energy, the resulting experimental efficiency value is about 70%.
The radiation hardness of polysiloxane based scintillators has been measured by ion beam induced luminescence (IBIL). The light intensity as a function of the irradiation fluence with an He
+ beam at ...1.8
MeV (1.0 μA/cm
2) has been measured on undoped polymers synthesized with different amounts of phenyl units and on polysiloxanes doped with two different dye molecules (BBOT and Lumogen Violet) sensitizing the scintillation yield.
Study of High-Energy Fission in Inverse Kinematics Mantovani, G.; Ramos, D.; Caamaño, M. ...
4th International Conference on Nuclear Structure and Dynamics (NSD), Venice, Italy,
2019, Volume:
223
Journal Article, Conference Proceeding
Peer reviewed
Open access
Fission at low excitation energy, is a process in which both macroscopic and microscopic aspects are involved. Some features in the total kinetic energy and in the N/Z distributions of the fragments, ...commonly associated with shell effects, came out in a series of recent experiments with high excitation energy fusionfission reactions in inverse kinematics. In the latest experiment of this campaign, a study of high-energy fission and quasi-fission between a
238
U beam and a series of light targets was carried out by using the aforementioned technique, in order to probe the role of the shell structure in these processes.
Polysiloxane-based scintillators are promising for employment in harsh environments, owing to their outstanding radiation resistance and thermal properties over the traditional plastics ...(polyvinyltoluene and polystyrene). In this work, cross-linked polydimethyl-co-diphenylsiloxane (PMPS) scintillators with 22% molar percentage of diphenylsiloxane units have been synthesised. 2,5-Diphenyloxazole and Lumogen Violet (BASF) were employed as primary and secondary fluor, respectively. Thermal neutrons sensitivity was achieved through the addition of 3% wt of ortho-carborane. Scintillation yield measurements were made by exciting with (241)Am alpha source samples with different concentrations of dye molecules. PMPS-based scintillators with ∼50% light yield as compared with the commercial plastic scintillator EJ212 were produced. The scintillation yield of the B-loaded samples under thermal neutrons was tested with a moderated Am-Be source and compared with the commercially available EJ254 (5% wt B). 2.2 MeV neutrons were produced by irradiating with a 4.0 MeV proton beam an LiF target, thus exploiting the reaction (7)Li(p,n)(7)Be. Time-of-flight measurements were performed to distinguish pulses due to neutrons or gamma. A similar test was performed with an EJ254 commercial scintillator for comparison. Using the same set-up, polyethylene bricks were used as a moderator to produce low-energy neutrons for testing B-loaded samples.
Pulse shape analysis of liquid scintillators for neutron studies Marrone, S; Cano-Ott, D; Colonna, N ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
09/2002, Volume:
490, Issue:
1
Journal Article
Peer reviewed
The acquisition of signals from liquid scintillators with Flash ADC of high sampling rate
(1
GS/
s)
has been investigated. The possibility to record the signal waveform is of great advantage in ...studies with γ's and neutrons in a high count-rate environment, as it allows to easily identify and separate pile-up events. The shapes of pulses produced by γ-rays and neutrons have been studied for two different liquid scintillators, NE213 and C
6D
6. A 1-parameter fitting procedure is proposed, which allows to extract information on the particle type and energy. The performance of this method in terms of energy resolution and n/γ discrimination is analyzed, together with the capability to identify and resolve pile-up events.
A STUDY ON 4 REACTIONS FORMING 46Ti Cicerchia, M.; Marchi, T.; Gramegna, F. ...
Journal of physics. Conference series,
02/2018, Volume:
966, Issue:
1
Journal Article
Peer reviewed
Open access
The NUCL-EX collaboration is carrying out an extensive research program on preequilibrium emission of light charged particles from hot nuclei. The ultimate goal is to study how cluster structures ...affect nuclear reactions 1,2,3,4. Indeed, a strong correlation between nuclear structure and reaction dynamics emerges when some nucleons or clusters of nucleons are emitted or captured 5. At this purpose, the four reactions 16O+30Si, 16O+30Si, 18O+28Si and 19F +27Al have been measured at about 120 MeV projectile energy. Experimental data were collected at Legnaro National Laboratories, using the GARFIELD+RCo array, fully equipped with digital electronics 6. Following an initial identification of particles and the energy calibration procedures, the complete analysis is being performed on an event-by-event basis. Experimental data are then compared to the theoretical predictions where events are generated by numerical codes based on pre-equilibrium and statistical models and then filtered through a software replica of the setup. Differences between the experimental data and the predicted data put into evidence effects related to the entrance channel and to the cluster nature of the colliding ions. After a general introduction on the experimental campaign, this contribution will focus on the preliminary results obtained so far.
In the recent years, cluster structures have been evidenced in many ground and excited states of light nuclei 1, 2. In the currently experimental campaign, the NUCL-EX collaboration has measured ...the12C+12C and14N+10B reactions at 95 MeV and 80 MeV respectively. The experimental data corresponding to complete fusion of target and projectile into an excited24Mg nucleus was compared to the results of a pure statistical model 3, 4. In addition, data from12C+12C have been analyzed to investigate the decay of the Hoyle state of12C* 12 obtained as an intermediate step in the 6α decay channel of the24Mg* formed in central events.
Clustering structural properties in medium-mass systems have been investigated studying the competition between the evaporation and pre-equilibrium particle emission in central collisions. At ...variance with light nuclei, in the case of heavier nuclei there are no experimental evidences of such structure effects, since the determination of pre-formed clusters within nuclear matter is less obvious. The two systems 16O + 65Cu and 19F + 62Ni, leading to the same compound system 81Rb*, have been studied at the same beam velocity (16 AMeV). The experiments have been performed using the GARFIELD + RCo multi-detection system at the Legnaro National Laboratories. Recent results of the data analysis and of the comparison of the experimental data with different statistical and dynamical model calculations are reported in this contribution.
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