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Papers by michele tonezzer

Research paper thumbnail of The SiC Direct Target Prototype for SPES

A R&D study for the realization of a Direct Target is in progress within the SPES project for... more A R&D study for the realization of a Direct Target is in progress within the SPES project for RIBs production at the Laboratori Nazionali of Legnaro. A proton beam (40 MeV energy, 0.2 mA current) is supposed to impinge directly on a UCx multiple thin disks target, the power ...

Research paper thumbnail of The UA9 experimental layout

Journal of Instrumentation, 2011

The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investi... more The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investigating crystal assisted collimation in coasting mode. Its basic layout comprises silicon bent crystals acting as primary collimators mounted inside two vacuum vessels. A movable 60 cm long block of tungsten located downstream at about 90 degrees phase advance intercepts the deflected beam. Scintillators, Gas Electron Multiplier chambers and other beam loss monitors measure nuclear loss rates induced by the interaction of the beam halo in the crystal. Roman pots are installed in the path of the deflected particles and are equipped with a Medipix detector to reconstruct the transverse distribution of the impinging beam. Finally UA9 takes advantage of an LHC-collimator prototype installed close to the Roman pot to help in setting the beam conditions and to analyze the efficiency to deflect the beam. This paper describes in details the hardware installed to study the crystal collimation during 2010.

Research paper thumbnail of The UA9 experimental layout

Journal of Instrumentation, 2011

The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investi... more The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investigating crystal assisted collimation in coasting mode. Its basic layout comprises silicon bent crystals acting as primary collimators mounted inside two vacuum vessels. A movable 60 cm long block of tungsten located downstream at about 90 degrees phase advance intercepts the deflected beam. Scintillators, Gas Electron Multiplier chambers and other beam loss monitors measure nuclear loss rates induced by the interaction of the beam halo in the crystal. Roman pots are installed in the path of the deflected particles and are equipped with a Medipix detector to reconstruct the transverse distribution of the impinging beam. Finally UA9 takes advantage of an LHC-collimator prototype installed close to the Roman pot to help in setting the beam conditions and to analyze the efficiency to deflect the beam. This paper describes in details the hardware installed to study the crystal collimation during 2010.

Research paper thumbnail of Release time calculations for the SPES direct UCx target

European Physical Journal-special Topics, 2007

A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework... more A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework of the R&D for the SPES project [1]. Using a 40 MeV proton beam impinging on a UCx thick target of 2.5 g/cm3 density, a production rate of 1013 in target fissions per second is expected [2]. The crucial point, when short-lived isotopes are produced in the target, is to build systems (target + ion source) with good release properties and high efficiency. Monte Carlo simulations were performed using the GEANT4 toolkit [3] and the RIBO code [4] in order to optimize our target geometry and to estimate the average release time.

Research paper thumbnail of Release time calculations for the SPES direct UCx target

European Physical Journal-special Topics, 2007

A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework... more A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework of the R&D for the SPES project [1]. Using a 40 MeV proton beam impinging on a UCx thick target of 2.5 g/cm3 density, a production rate of 1013 in target fissions per second is expected [2]. The crucial point, when short-lived isotopes are produced in the target, is to build systems (target + ion source) with good release properties and high efficiency. Monte Carlo simulations were performed using the GEANT4 toolkit [3] and the RIBO code [4] in order to optimize our target geometry and to estimate the average release time.

Research paper thumbnail of The Spes Direct Target Project at the Laboratori Nazionali DI Legnaro

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the ... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama. The SPES Project aims for the production of neutron-rich unstable nuclei by the fission of natural Uranium target induced by a primary proton beam of 40 MeV, 200 μA directly impinging on a multi-sliced Uranium Carbide (UCx) target. The idea is an evolution of the existing HRIBF facility at Oak Ridge National Laboratory (USA) where a proton primary beam of 40 MeV is also used. The goal is to reach a high number of fission products (up to 1013 fission/s) still keeping a relatively low power deposition inside the target. The description of the whole facility, together with the details on the Direct Target configuration, will be illustrated. Thermo-mechanical calculations, pellets preparation and characterization, effusion-diffusion model predictions for the estimation of the release fraction of different radioactive nuclides will be discussed. A scaled (1:5) prototype of the Target system has been built and tested recently at HRIBF.

Research paper thumbnail of The Spes Direct Target Project at the Laboratori Nazionali DI Legnaro

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the ... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama. The SPES Project aims for the production of neutron-rich unstable nuclei by the fission of natural Uranium target induced by a primary proton beam of 40 MeV, 200 μA directly impinging on a multi-sliced Uranium Carbide (UCx) target. The idea is an evolution of the existing HRIBF facility at Oak Ridge National Laboratory (USA) where a proton primary beam of 40 MeV is also used. The goal is to reach a high number of fission products (up to 1013 fission/s) still keeping a relatively low power deposition inside the target. The description of the whole facility, together with the details on the Direct Target configuration, will be illustrated. Thermo-mechanical calculations, pellets preparation and characterization, effusion-diffusion model predictions for the estimation of the release fraction of different radioactive nuclides will be discussed. A scaled (1:5) prototype of the Target system has been built and tested recently at HRIBF.

Research paper thumbnail of Preliminary radiation protection analyses of the target SPES

Research paper thumbnail of Preliminary radiation protection analyses of the target SPES

Research paper thumbnail of Calculations and first results obtained with a SiC prototype of the SPES direct target

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 20... more In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 2002], the realization of a direct ISOL Target for a mid-term radioactive ion beam facility is in progress. Using a primary proton beam of energy 40 MeV and intensity 0.2 mA, a high number of fission products will be obtained in the SPES multi-foil uranium carbide target, keeping a low power density deposition in the refractory matrix [A. Andrighetto, S. Cevolani, C. Petrovich, Eur. Phys J. A 25 ]. The exotic species produced by Uranium fission in the target are collected in the ion source after the diffusion and the effusion processes. When short lived isotopes are produced it is very important to optimize the release properties of the target. To this purpose the RIBO code (radioactive ion beam optimiser) [M. Santana Leitner, A Monte Carlo Code to Optimize the Production of Radioactive Ion Beams by the ISOL Technique, PhD. Thesis, UPC-ETSEIB/CERN] has been used in order to estimate the target release efficiency for some neutron-rich nuclei. A SiC prototype of the target was recently produced at LNL and tested at ORNL using a 42 MeV proton beam. The yield of some aluminum isotopes was measured as a function of the target temperature. Some preliminary results of the data analysis will be presented.

Research paper thumbnail of Calculations and first results obtained with a SiC prototype of the SPES direct target

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 20... more In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 2002], the realization of a direct ISOL Target for a mid-term radioactive ion beam facility is in progress. Using a primary proton beam of energy 40 MeV and intensity 0.2 mA, a high number of fission products will be obtained in the SPES multi-foil uranium carbide target, keeping a low power density deposition in the refractory matrix [A. Andrighetto, S. Cevolani, C. Petrovich, Eur. Phys J. A 25 ]. The exotic species produced by Uranium fission in the target are collected in the ion source after the diffusion and the effusion processes. When short lived isotopes are produced it is very important to optimize the release properties of the target. To this purpose the RIBO code (radioactive ion beam optimiser) [M. Santana Leitner, A Monte Carlo Code to Optimize the Production of Radioactive Ion Beams by the ISOL Technique, PhD. Thesis, UPC-ETSEIB/CERN] has been used in order to estimate the target release efficiency for some neutron-rich nuclei. A SiC prototype of the target was recently produced at LNL and tested at ORNL using a 42 MeV proton beam. The yield of some aluminum isotopes was measured as a function of the target temperature. Some preliminary results of the data analysis will be presented.

Research paper thumbnail of Studies of uranium carbide targets of a high density

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investig... more Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investigated at IRIS (Investigation Radioactive Isotopes at Synchrocyclotron), Gatchina. The UC target material with a density of 12 g/cm 3 was prepared in a form of pellets. Two targets were tested on-line under the same temperature conditions: (a) a reference small target with a thickness of 4.5 g/cm 2 ; (b) a heavier (so called intermediate) target with a thickness of 91 g/cm 2 . Yields and release efficiencies of nuclides with half-lives from some minutes to some milliseconds produced by 1 GeV protons in these targets are presented. It is remarkable that yields, even those of very short-lived isotopes such as 214 Fr (T 1/2 = 5 ms) and 219 Fr (T 1/2 = 20 ms), increase proportionally to the target thickness. A one month off-line heating test of the 91 g/cm 2 target at a temperature of 2000°C has been carried out successfully. The yields and release efficiencies of Cs and Fr measured on-line before and after the heating test coincided within the limits of measurement errors, thereby demonstrating the conservation of the target unit parameters. Based on these very promising results, a heavier target with a mass about 0.7 kg is prepared presently at IRIS.

Research paper thumbnail of Studies of uranium carbide targets of a high density

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investig... more Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investigated at IRIS (Investigation Radioactive Isotopes at Synchrocyclotron), Gatchina. The UC target material with a density of 12 g/cm 3 was prepared in a form of pellets. Two targets were tested on-line under the same temperature conditions: (a) a reference small target with a thickness of 4.5 g/cm 2 ; (b) a heavier (so called intermediate) target with a thickness of 91 g/cm 2 . Yields and release efficiencies of nuclides with half-lives from some minutes to some milliseconds produced by 1 GeV protons in these targets are presented. It is remarkable that yields, even those of very short-lived isotopes such as 214 Fr (T 1/2 = 5 ms) and 219 Fr (T 1/2 = 20 ms), increase proportionally to the target thickness. A one month off-line heating test of the 91 g/cm 2 target at a temperature of 2000°C has been carried out successfully. The yields and release efficiencies of Cs and Fr measured on-line before and after the heating test coincided within the limits of measurement errors, thereby demonstrating the conservation of the target unit parameters. Based on these very promising results, a heavier target with a mass about 0.7 kg is prepared presently at IRIS.

Research paper thumbnail of The SPES Direct Target Project at LNL

Acta Physica Polonica B, 2007

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the con... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama, is presented. An innovative configuration for the SPES Project, for the production of neutron-rich exotic nuclei, proposes the use of a primary proton beam (40 MeV, 0.2 mA), directly impinging on a large Multi-Slice Uranium Carbide Direct Target. The goal is to reach a high number of fission products (up to 1013 fissions/s), still keeping a quite low power deposition inside the target. The description of the overall facility together with details on the Direct Target configuration is presented. Thermo-mechanical calculations, material preparation and characterisation, effusion--diffusion model predictions for the estimation of the release time and total release fraction for different life times and isotopes will be discussed. Finally, a scaled (1:5) prototype of the Target System built to be tested and compared under existing proton beam facilities, will be described.

Research paper thumbnail of The SPES Direct Target Project at LNL

Acta Physica Polonica B, 2007

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the con... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama, is presented. An innovative configuration for the SPES Project, for the production of neutron-rich exotic nuclei, proposes the use of a primary proton beam (40 MeV, 0.2 mA), directly impinging on a large Multi-Slice Uranium Carbide Direct Target. The goal is to reach a high number of fission products (up to 1013 fissions/s), still keeping a quite low power deposition inside the target. The description of the overall facility together with details on the Direct Target configuration is presented. Thermo-mechanical calculations, material preparation and characterisation, effusion--diffusion model predictions for the estimation of the release time and total release fraction for different life times and isotopes will be discussed. Finally, a scaled (1:5) prototype of the Target System built to be tested and compared under existing proton beam facilities, will be described.

Research paper thumbnail of On the fabrication process of polymer-composites based sensors

The results of investigations of the effects of two organic solvents of preparation, tetrahydrofu... more The results of investigations of the effects of two organic solvents of preparation, tetrahydrofuran (THF) and 1,1,1,3,3,3 Hexafluoro-2-propanol (HFIP), and of three different electrical geometry of devices on drop-coated poly (methyl-methacrylate)/ carbon black (PMMA/CB) composites gas sensors are presented. Using HFIP solvent, it is possible to obtain a good dispersion of the CB filler in the polymeric matrix but the thermodynamic responses of devices to acetone and ethanol vapours are independent from their morphology and from the geometry of devices. The highest sensor responses are to acetone vapor. This behavior could be probably attributed to the higher chemical affinity of less polar molecule as acetone towards PMMA. The filler dispersions, the current-voltage (I/V) characteristics and the stability of devices in the time were also studied and discussed.

Research paper thumbnail of The SPES Direct Target Project at the Laboratori Nazionali di Legnaro

Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE ... more Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE Laboratori Nazionali di Legnaro, viale dell'Universitd 2 Legnaro, 35020 Italy A. ANDRIGHETTO1, C ...

Research paper thumbnail of The SPES Direct Target Project at the Laboratori Nazionali di Legnaro

Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE ... more Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE Laboratori Nazionali di Legnaro, viale dell'Universitd 2 Legnaro, 35020 Italy A. ANDRIGHETTO1, C ...

Research paper thumbnail of Comparative results on collimation of the SPS beam of protons and Pb ions with bent crystals

Physics Letters B, 2011

New experiments on crystal assisted collimation have been carried out at the CERN SPS with stored... more New experiments on crystal assisted collimation have been carried out at the CERN SPS with stored beams of 120 GeV/c protons and Pb ions. Bent silicon crystals of 2 mm long with about 170 μrad bend angle and a small residual torsion were used as primary collimators. In channeling conditions, the beam loss rate induced by inelastic interactions of particles with the crystal nuclei is minimal. The loss reduction was about 6 for protons and about 3 for Pb ions. Lower reduction value for Pb ions can be explained by their considerably larger ionization losses in the crystal. In one of the crystals, the measured fraction of the Pb ion beam halo deflected in channeling conditions was 74%, a value very close to that for protons. The intensity of the off-momentum halo leaking out from the collimation station was measured in the first high dispersion area downstream. The particle population in the shadow of the secondary collimator-absorber was considerably smaller in channeling conditions than for amorphous orientations of the crystal. The corresponding reduction was in the range of 2-5 for both protons and Pb ions.

Research paper thumbnail of 2008

Studies of uranium carbide targets of a high density, Nuclear Instruments and Methods in Physic R... more Studies of uranium carbide targets of a high density, Nuclear Instruments and Methods in Physic Research B 266 (2008) 4247-4251. 2. Tests of high-density UC targets developed at Gatchina for neutron-rich radioactive beam facilities, accepted for Nucl. Instr. and Meth. in Phys. Res. B.

Research paper thumbnail of The SiC Direct Target Prototype for SPES

A R&D study for the realization of a Direct Target is in progress within the SPES project for... more A R&D study for the realization of a Direct Target is in progress within the SPES project for RIBs production at the Laboratori Nazionali of Legnaro. A proton beam (40 MeV energy, 0.2 mA current) is supposed to impinge directly on a UCx multiple thin disks target, the power ...

Research paper thumbnail of The UA9 experimental layout

Journal of Instrumentation, 2011

The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investi... more The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investigating crystal assisted collimation in coasting mode. Its basic layout comprises silicon bent crystals acting as primary collimators mounted inside two vacuum vessels. A movable 60 cm long block of tungsten located downstream at about 90 degrees phase advance intercepts the deflected beam. Scintillators, Gas Electron Multiplier chambers and other beam loss monitors measure nuclear loss rates induced by the interaction of the beam halo in the crystal. Roman pots are installed in the path of the deflected particles and are equipped with a Medipix detector to reconstruct the transverse distribution of the impinging beam. Finally UA9 takes advantage of an LHC-collimator prototype installed close to the Roman pot to help in setting the beam conditions and to analyze the efficiency to deflect the beam. This paper describes in details the hardware installed to study the crystal collimation during 2010.

Research paper thumbnail of The UA9 experimental layout

Journal of Instrumentation, 2011

The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investi... more The UA9 experimental equipment was installed in the CERN-SPS in March '09 with the aim of investigating crystal assisted collimation in coasting mode. Its basic layout comprises silicon bent crystals acting as primary collimators mounted inside two vacuum vessels. A movable 60 cm long block of tungsten located downstream at about 90 degrees phase advance intercepts the deflected beam. Scintillators, Gas Electron Multiplier chambers and other beam loss monitors measure nuclear loss rates induced by the interaction of the beam halo in the crystal. Roman pots are installed in the path of the deflected particles and are equipped with a Medipix detector to reconstruct the transverse distribution of the impinging beam. Finally UA9 takes advantage of an LHC-collimator prototype installed close to the Roman pot to help in setting the beam conditions and to analyze the efficiency to deflect the beam. This paper describes in details the hardware installed to study the crystal collimation during 2010.

Research paper thumbnail of Release time calculations for the SPES direct UCx target

European Physical Journal-special Topics, 2007

A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework... more A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework of the R&D for the SPES project [1]. Using a 40 MeV proton beam impinging on a UCx thick target of 2.5 g/cm3 density, a production rate of 1013 in target fissions per second is expected [2]. The crucial point, when short-lived isotopes are produced in the target, is to build systems (target + ion source) with good release properties and high efficiency. Monte Carlo simulations were performed using the GEANT4 toolkit [3] and the RIBO code [4] in order to optimize our target geometry and to estimate the average release time.

Research paper thumbnail of Release time calculations for the SPES direct UCx target

European Physical Journal-special Topics, 2007

A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework... more A Direct Target for a mid-term RIB ISOL-type facility is being developed at LNL, in the framework of the R&D for the SPES project [1]. Using a 40 MeV proton beam impinging on a UCx thick target of 2.5 g/cm3 density, a production rate of 1013 in target fissions per second is expected [2]. The crucial point, when short-lived isotopes are produced in the target, is to build systems (target + ion source) with good release properties and high efficiency. Monte Carlo simulations were performed using the GEANT4 toolkit [3] and the RIBO code [4] in order to optimize our target geometry and to estimate the average release time.

Research paper thumbnail of The Spes Direct Target Project at the Laboratori Nazionali DI Legnaro

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the ... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama. The SPES Project aims for the production of neutron-rich unstable nuclei by the fission of natural Uranium target induced by a primary proton beam of 40 MeV, 200 μA directly impinging on a multi-sliced Uranium Carbide (UCx) target. The idea is an evolution of the existing HRIBF facility at Oak Ridge National Laboratory (USA) where a proton primary beam of 40 MeV is also used. The goal is to reach a high number of fission products (up to 1013 fission/s) still keeping a relatively low power deposition inside the target. The description of the whole facility, together with the details on the Direct Target configuration, will be illustrated. Thermo-mechanical calculations, pellets preparation and characterization, effusion-diffusion model predictions for the estimation of the release fraction of different radioactive nuclides will be discussed. A scaled (1:5) prototype of the Target system has been built and tested recently at HRIBF.

Research paper thumbnail of The Spes Direct Target Project at the Laboratori Nazionali DI Legnaro

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the ... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), is devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama. The SPES Project aims for the production of neutron-rich unstable nuclei by the fission of natural Uranium target induced by a primary proton beam of 40 MeV, 200 μA directly impinging on a multi-sliced Uranium Carbide (UCx) target. The idea is an evolution of the existing HRIBF facility at Oak Ridge National Laboratory (USA) where a proton primary beam of 40 MeV is also used. The goal is to reach a high number of fission products (up to 1013 fission/s) still keeping a relatively low power deposition inside the target. The description of the whole facility, together with the details on the Direct Target configuration, will be illustrated. Thermo-mechanical calculations, pellets preparation and characterization, effusion-diffusion model predictions for the estimation of the release fraction of different radioactive nuclides will be discussed. A scaled (1:5) prototype of the Target system has been built and tested recently at HRIBF.

Research paper thumbnail of Preliminary radiation protection analyses of the target SPES

Research paper thumbnail of Preliminary radiation protection analyses of the target SPES

Research paper thumbnail of Calculations and first results obtained with a SiC prototype of the SPES direct target

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 20... more In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 2002], the realization of a direct ISOL Target for a mid-term radioactive ion beam facility is in progress. Using a primary proton beam of energy 40 MeV and intensity 0.2 mA, a high number of fission products will be obtained in the SPES multi-foil uranium carbide target, keeping a low power density deposition in the refractory matrix [A. Andrighetto, S. Cevolani, C. Petrovich, Eur. Phys J. A 25 ]. The exotic species produced by Uranium fission in the target are collected in the ion source after the diffusion and the effusion processes. When short lived isotopes are produced it is very important to optimize the release properties of the target. To this purpose the RIBO code (radioactive ion beam optimiser) [M. Santana Leitner, A Monte Carlo Code to Optimize the Production of Radioactive Ion Beams by the ISOL Technique, PhD. Thesis, UPC-ETSEIB/CERN] has been used in order to estimate the target release efficiency for some neutron-rich nuclei. A SiC prototype of the target was recently produced at LNL and tested at ORNL using a 42 MeV proton beam. The yield of some aluminum isotopes was measured as a function of the target temperature. Some preliminary results of the data analysis will be presented.

Research paper thumbnail of Calculations and first results obtained with a SiC prototype of the SPES direct target

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 20... more In the framework of the SPES project at LNL [A. Bracco, A. Pisent (Ed.), REP 181/02, LNL-INFN, 2002], the realization of a direct ISOL Target for a mid-term radioactive ion beam facility is in progress. Using a primary proton beam of energy 40 MeV and intensity 0.2 mA, a high number of fission products will be obtained in the SPES multi-foil uranium carbide target, keeping a low power density deposition in the refractory matrix [A. Andrighetto, S. Cevolani, C. Petrovich, Eur. Phys J. A 25 ]. The exotic species produced by Uranium fission in the target are collected in the ion source after the diffusion and the effusion processes. When short lived isotopes are produced it is very important to optimize the release properties of the target. To this purpose the RIBO code (radioactive ion beam optimiser) [M. Santana Leitner, A Monte Carlo Code to Optimize the Production of Radioactive Ion Beams by the ISOL Technique, PhD. Thesis, UPC-ETSEIB/CERN] has been used in order to estimate the target release efficiency for some neutron-rich nuclei. A SiC prototype of the target was recently produced at LNL and tested at ORNL using a 42 MeV proton beam. The yield of some aluminum isotopes was measured as a function of the target temperature. Some preliminary results of the data analysis will be presented.

Research paper thumbnail of Studies of uranium carbide targets of a high density

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investig... more Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investigated at IRIS (Investigation Radioactive Isotopes at Synchrocyclotron), Gatchina. The UC target material with a density of 12 g/cm 3 was prepared in a form of pellets. Two targets were tested on-line under the same temperature conditions: (a) a reference small target with a thickness of 4.5 g/cm 2 ; (b) a heavier (so called intermediate) target with a thickness of 91 g/cm 2 . Yields and release efficiencies of nuclides with half-lives from some minutes to some milliseconds produced by 1 GeV protons in these targets are presented. It is remarkable that yields, even those of very short-lived isotopes such as 214 Fr (T 1/2 = 5 ms) and 219 Fr (T 1/2 = 20 ms), increase proportionally to the target thickness. A one month off-line heating test of the 91 g/cm 2 target at a temperature of 2000°C has been carried out successfully. The yields and release efficiencies of Cs and Fr measured on-line before and after the heating test coincided within the limits of measurement errors, thereby demonstrating the conservation of the target unit parameters. Based on these very promising results, a heavier target with a mass about 0.7 kg is prepared presently at IRIS.

Research paper thumbnail of Studies of uranium carbide targets of a high density

Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 2008

Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investig... more Production of Cs and Fr isotopes from uranium carbide targets of a high density has been investigated at IRIS (Investigation Radioactive Isotopes at Synchrocyclotron), Gatchina. The UC target material with a density of 12 g/cm 3 was prepared in a form of pellets. Two targets were tested on-line under the same temperature conditions: (a) a reference small target with a thickness of 4.5 g/cm 2 ; (b) a heavier (so called intermediate) target with a thickness of 91 g/cm 2 . Yields and release efficiencies of nuclides with half-lives from some minutes to some milliseconds produced by 1 GeV protons in these targets are presented. It is remarkable that yields, even those of very short-lived isotopes such as 214 Fr (T 1/2 = 5 ms) and 219 Fr (T 1/2 = 20 ms), increase proportionally to the target thickness. A one month off-line heating test of the 91 g/cm 2 target at a temperature of 2000°C has been carried out successfully. The yields and release efficiencies of Cs and Fr measured on-line before and after the heating test coincided within the limits of measurement errors, thereby demonstrating the conservation of the target unit parameters. Based on these very promising results, a heavier target with a mass about 0.7 kg is prepared presently at IRIS.

Research paper thumbnail of The SPES Direct Target Project at LNL

Acta Physica Polonica B, 2007

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the con... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama, is presented. An innovative configuration for the SPES Project, for the production of neutron-rich exotic nuclei, proposes the use of a primary proton beam (40 MeV, 0.2 mA), directly impinging on a large Multi-Slice Uranium Carbide Direct Target. The goal is to reach a high number of fission products (up to 1013 fissions/s), still keeping a quite low power deposition inside the target. The description of the overall facility together with details on the Direct Target configuration is presented. Thermo-mechanical calculations, material preparation and characterisation, effusion--diffusion model predictions for the estimation of the release time and total release fraction for different life times and isotopes will be discussed. Finally, a scaled (1:5) prototype of the Target System built to be tested and compared under existing proton beam facilities, will be described.

Research paper thumbnail of The SPES Direct Target Project at LNL

Acta Physica Polonica B, 2007

The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the con... more The SPES Direct Target Project at the Laboratori Nazionali di Legnaro (Italy), devoted to the construction of a Radioactive Ion Beam (RIB) Facility within the framework of the new European RIB panorama, is presented. An innovative configuration for the SPES Project, for the production of neutron-rich exotic nuclei, proposes the use of a primary proton beam (40 MeV, 0.2 mA), directly impinging on a large Multi-Slice Uranium Carbide Direct Target. The goal is to reach a high number of fission products (up to 1013 fissions/s), still keeping a quite low power deposition inside the target. The description of the overall facility together with details on the Direct Target configuration is presented. Thermo-mechanical calculations, material preparation and characterisation, effusion--diffusion model predictions for the estimation of the release time and total release fraction for different life times and isotopes will be discussed. Finally, a scaled (1:5) prototype of the Target System built to be tested and compared under existing proton beam facilities, will be described.

Research paper thumbnail of On the fabrication process of polymer-composites based sensors

The results of investigations of the effects of two organic solvents of preparation, tetrahydrofu... more The results of investigations of the effects of two organic solvents of preparation, tetrahydrofuran (THF) and 1,1,1,3,3,3 Hexafluoro-2-propanol (HFIP), and of three different electrical geometry of devices on drop-coated poly (methyl-methacrylate)/ carbon black (PMMA/CB) composites gas sensors are presented. Using HFIP solvent, it is possible to obtain a good dispersion of the CB filler in the polymeric matrix but the thermodynamic responses of devices to acetone and ethanol vapours are independent from their morphology and from the geometry of devices. The highest sensor responses are to acetone vapor. This behavior could be probably attributed to the higher chemical affinity of less polar molecule as acetone towards PMMA. The filler dispersions, the current-voltage (I/V) characteristics and the stability of devices in the time were also studied and discussed.

Research paper thumbnail of The SPES Direct Target Project at the Laboratori Nazionali di Legnaro

Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE ... more Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE Laboratori Nazionali di Legnaro, viale dell'Universitd 2 Legnaro, 35020 Italy A. ANDRIGHETTO1, C ...

Research paper thumbnail of The SPES Direct Target Project at the Laboratori Nazionali di Legnaro

Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE ... more Page 134. THE SPES DIRECT TARGET PROJECT AT THE LABORATORI NAZIONALI DI LEGNARO GIANFRANCO PRETE Laboratori Nazionali di Legnaro, viale dell'Universitd 2 Legnaro, 35020 Italy A. ANDRIGHETTO1, C ...

Research paper thumbnail of Comparative results on collimation of the SPS beam of protons and Pb ions with bent crystals

Physics Letters B, 2011

New experiments on crystal assisted collimation have been carried out at the CERN SPS with stored... more New experiments on crystal assisted collimation have been carried out at the CERN SPS with stored beams of 120 GeV/c protons and Pb ions. Bent silicon crystals of 2 mm long with about 170 μrad bend angle and a small residual torsion were used as primary collimators. In channeling conditions, the beam loss rate induced by inelastic interactions of particles with the crystal nuclei is minimal. The loss reduction was about 6 for protons and about 3 for Pb ions. Lower reduction value for Pb ions can be explained by their considerably larger ionization losses in the crystal. In one of the crystals, the measured fraction of the Pb ion beam halo deflected in channeling conditions was 74%, a value very close to that for protons. The intensity of the off-momentum halo leaking out from the collimation station was measured in the first high dispersion area downstream. The particle population in the shadow of the secondary collimator-absorber was considerably smaller in channeling conditions than for amorphous orientations of the crystal. The corresponding reduction was in the range of 2-5 for both protons and Pb ions.

Research paper thumbnail of 2008

Studies of uranium carbide targets of a high density, Nuclear Instruments and Methods in Physic R... more Studies of uranium carbide targets of a high density, Nuclear Instruments and Methods in Physic Research B 266 (2008) 4247-4251. 2. Tests of high-density UC targets developed at Gatchina for neutron-rich radioactive beam facilities, accepted for Nucl. Instr. and Meth. in Phys. Res. B.