Paolo Finocchiaro

Recent developments of the EXCYT project

Abstract The aim of the EXCYT project is to develop a facility for the production and the acceleration of exotic beams up to 8 MeV/amu. The primary beams shall be provided by the now operational K-800 superconducting cyclotron and the exotic ions will be accelerated by a 15 MV Tandem. We will describe the cyclotron source and its axial injection system, the transfer beam line sending the primary beams onto the target and the target-ion source unit. Also we will describe the planned high resolution isobar separator that should allow to perform either nuclear or astrophysical and material science experiments. This separator consists of a pre-separator and two main stages and should provide an overall mass resolving power up to m/Dm ≈ 20000.

A scintillating fibre-based profiler for low intensity ion beams

Abstract In the framework of the EXCYT radioactive ion beams facility, now under development at LNS Catania, we have developed a new beam profile monitor based on a scintillating fibre and a photodetector. Its sensitivity allows the detection of single beam particles in pulse mode, thus representing a useful tool for diagnostics of low and very low intensity beams.

The data acquisition system for the crystal ball at LNS

Abstract In this paper we describe the actual status of the data acquisition system for the Crystal Ball 4π detector to be installed at LNS. We describe in some detail the open architecture required to ensure the possible future extensions of the system. Noticeable is the fact that this system is not bound to any particular kind of computer or software: the only fixed components of the architecture are the VME-bus for the computer systems and the FERA-bus for the fast transfer of the digitalized data.

The ISOL exotic beam facility at LNS: the EXCYT project

Abstract The aim of the EXCYT project (EXotics with CYclotron and Tandem) is the development of a facility for producing and accelerating exotic beams from 0.2 up to 8 MeV/amu. EXCYT is based on the “two accelerators” method. A K = 800 Superconducting Cyclotron (CS), axially injected by the ECR ion source SERSE, will deliver the primary beam. Such a beam will produce the required nuclear species in a modified ISOLDE type target-source complex. When required, a 15 MV Tandem Van der Graaff will accelerate the secondary beams. Both accelerators are existing and operational at Laboratorio Nazionale del Sud (LNS). Concerning the status of the project, progress has been made in most of the key issues of the project, like the construction of SERSE, cyclotron upgrading, modification of the existing building, high resolution mass separator, and diagnostic equipment for low energy, low intensity beams.

Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

Silicon Photomultipliers for nuclear medical imaging applications

In this contribution we present the results of the first morphological and electro-optical characterization of Silicon Photomultipliers (SiPM) for nuclear medical imaging applications fabricated in standard silicon planar technology at the STMicroelectronics Catania R&D clean room facility. We have improved our previous Geiger Mode Avalanche Photodiodes (GMAP) technology in order to realize a photodetector with relevant features in terms of single-photoelectron resolution, timing and photon detection efficiency. The performances of our devices, investigated in several experimental conditions and here reported make ST-SiPM suitable in many applications like for example PET (Positron Emission Tomography).

Ion micro-beam diagnostics with photodetectors

We have developed two techniques for microscopic ion beam imaging and profiling, both based on scintillators, particularly suitable for applications in deep lithography with protons (DLP) or with heavier ions. The first one employs a scintillating fiberoptic plate and a CCD camera with suitable lenses, the second makes use of a small scintillator optically coupled to a compact photomultiplier. We have proved the possibility of spanning from single beam particles counting up to several nA currents. Both the devices are successfully exploited for on-line control of proton beams, down to a beam size of less than 50 μm, in the framework of DLP application.

Status of the EXCYT facility at INFN-LNS

Abstract The EXCYT facility at the INFN-LNS aims to the production of radioactive ion beams to be post-accelerated by a 15xa0MV Tandem. The primary stable heavy-ion beam (up to 80xa0MeV/amu, 1xa0pμA) is supplied by a K-800 Superconducting Cyclotron, which has been operating in a stand-alone mode, by means of the new axial injection beam line, since December, 1999. The magnets of the primary beam line have been aligned and most of the components of the mass separator have been purchased. Different types of Heavy Ion Target–Source (HITS) systems have been built and are here described; in particular, a microwave ion source fully designed and manufactured at LNS has been assembled and successfully tested. Finally, low-intensity beam diagnostics is also ready and reliability tests are under way.

A portable data acquisition system for detector development, test and calibration

Abstract A small data acquisition system is described, suitable to be easily moved in order to test nuclear particle or radiation detectors both on-site and on the testing bench. Due to its features it can be considered a trans-multichannel analyzer (TMA), because it stands between a multichannel analyzer and a true data acquisition system for experiments.

LOW INTENSITY ION BEAM PROFILING WITH GLASS SCINTILLATING FIBRES

Abstract We report on the test results obtained with a prototype beam profiler based on a glass scintillating fibre and a compact photomultiplier, particularly suitable for the low intensity beam diagnostics needed in the framework of the EXCYT radioactive ion beam facility currently under development at the LNS in Catania.