Calculations and first results obtained with a SiC prototype of the SPES direct target (original) (raw)

Neutron-rich isotope production using the uranium carbide multi-foil SPES target prototype

The European Physical Journal A, 2011

The SPES (Selective Production of Exotic Species) project, under development at the Istituto Nazionale di Fisica Nucleare -Laboratori Nazionali di Legnaro (INFN-LNL), is a new-generation Isotope Separation On-Line (ISOL) facility for the production of radioactive ion beams by means of the protoninduced fission of uranium. In the framework of the research on the SPES target, seven uranium carbide discs, obtained by reacting uranium oxide with graphite and carbon nanotubes, were irradiated with protons at the Holifield Radioactive Ion Beam Facility (HRIBF) of Oak Ridge National Laboratory (ORNL). In the following, the yields of several fission products obtained during the experiment are presented and discussed. The experimental results are then compared to those obtained using a standard uranium carbide target. The reported data highlights the capability of the new type of SPES target to produce and release isotopes of interest for the nuclear physics community.

The SPES Direct Target Project at LNL

Acta Physica Polonica B - ACTA PHYS POL B, 2007

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 bui...

Development of uranium carbide targets for the on-line production of neutron-rich isotopes

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2005

A number of on-line and off-line tests have been performed at the IRIS (investigation of radioactive isotopes at synchrocyclotron) facility in order to develop uranium carbide targets with a high density (11 g/cm 3 ) for the on-line production of neutron-rich isotopes by fission of 238 U. A 1 GeV proton beam was used to bombard two kinds of targets held at temperatures in the range of 1900-2100°C. The first one was a target-ion source assembly slightly modified to withstand 3 months of continuous heating at a temperature of about 2050°C. The second unit was of a new kind, where ionisation takes place in the target volume itself. A comparison of the on-line isotopic yields before and after heating for 3 months is here reported. The yields and release times of Rb, Cs and In are compared with the ones obtained from a standard reference target, as measured in previous experiments. (V.N. Panteleev), dfedorov@pnpi.spb.ru (D.V. Fedorov). Nuclear Instruments and Methods in Physics Research B 240 (2005) 888-894 www.elsevier.com/locate/nimb PACS: 25.40.Sc; 28.60.+S; 29.25.Ni; 29.25.Rn

Research and development on materials for the SPES target

EPJ Web of Conferences, 2014

The SPES project at INFN-LNL (Istituto Nazionale di Fisica Nucleare-Laboratori Nazionali di Legnaro) is focused on the production of radioactive ion beams. The core of the SPES facility is constituted by the target, which will be irradiated with a 40 MeV, 200 µA proton beam in order to produce radioactive species. In order to efficiently produce and release isotopes, the material constituting the target should be able to work under extreme conditions (high vacuum and temperatures up to 2000 • C). Both neutronrich and proton-rich isotopes will be produced; in the first case, carbon dispersed uranium carbide (UC x) will be used as a target, whereas to produce p-rich isotopes, several types of targets will have to be irradiated. The synthesis and characterization of different types of material will be reported. Moreover, the results of irradiation and isotopes release tests on different uranium carbide target prototypes will be discussed.

The SPES Radioactive Ion Beam facility of INFN

Journal of Physics: Conference Series, 2015

A new Radioactive Ion Beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 40 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions are produced by proton induced fission at an expected fission rate of the order of 10 13 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV for masses in the region A=130 amu. The expected secondary beam rates are of the order of 10 7-10 9 pps. Aim of the SPES facility is to deliver high intensity radioactive ion beams of neutron rich nuclei for nuclear physics research as well as to be an interdisciplinary research center for radio-isotopes production for medicine and for neutron beams.

The SPES radioactive ion beam project of INFN

Journal of Physics: Conference Series, 2014

The SPES Radioactive Ion Beam facility at INFN-LNL is presently in the construction phase. The facility is based on the Isol (Isotope separation on-line) method with an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions are produced by proton induced Uranium fission at an expected fission rate of the order of 10 13 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting Linac at energies of 10A MeV for masses in the region A = 130 amu. The expected secondary beam rates are of the order of 10 7-10 9 pps. Aim of the SPES project is to provide a facility for high intensity radioactive ion beams for nuclear physics research as well as to develop an interdisciplinary research center based on the cyclotron proton beam.

Uranium carbide fission target R&D for RIA - an update

Nuclear Physics A, 2004

For the Rare Isotope Accelerator (RIA) facility, ISOL targets employing refractory compounds of uranium are being developed to produce radioactive ions for post-acceleration. The availability of refractory uranium compounds in forms that have good thermal conductivity, relatively high density, and adequate release properties for short-lived isotopes remains an important issue. Investigations using commercially obtained uranium carbide material and prepared into targets involving various binder materials have been carried out at ANL. Thin sample pellets have been produced for measurements of thermal conductivity using a new method based on electron bombardment with the thermal radiation observed using a two-color optical pyrometer and performed on samples as a function of grain size, pressing pressure and sintering temperature. Manufacture of uranium carbide powder has now been achieved at ANL. Simulations have been carried out on the thermal behavior of the secondary target assembly incorporating various heat shield configurations.

The SPES radioactive ion beam project of LNL: status and perspectives

EPJ Web of Conferences, 2016

A new Radioactive Ion Beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using an UCx Direct Target able to sustain a power of 8 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.2-0.7 mA. Neutron-rich radioactive ions are produced by proton induced fission on an Uranium target at an expected fission rate of the order of 10 13 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV for masses in the region A=130 amu. The expected secondary beam rates are of the order of 10 7-10 9 pps. Aim of the SPES facility is to deliver high intensity radioactive ion beams of neutron rich nuclei for nuclear physics research as well as to be an interdisciplinary research centre for radio-isotopes production for medicine and for neutron beams.

On-line production of Rb and Cs isotopes from uranium carbide targets

The European Physical Journal A, 2005

A series of on-line mass separation experiments have been performed at the IRIS facility to measure the yield and release of Rb and Cs neutron-rich isotopes produced by fission reaction of 238 U. A 1 GeV proton beam was used to bombard uranium carbide targets with the densities of 11 g/cm 3 and 1.5 g/cm 3 held at temperatures in the range (2000-2230) • C. The release curves of Rb and Cs long-lived isotopes were measured from both kinds of targets. The overall production efficiency was determined making use of experimentally measured cross-sections of that isotope production. Comparison of the experimental yields of Rb and Cs isotopes with the calculated ones after corrections for losses due to finite release times suggests that the diffusion is the dominating process reducing the efficiency for short-lived isotopes. When normalized to the same thickness, an enhancement for the high-density rod target of the measured isotope yields is observed when going far from stability. This is possibly explained by the reactions induced by secondary neutrons. A significant odd-even effect with higher yields of Cs even neutron isotopes has been observed, confirming a similar effect obtained in earlier experiments.