International Topical Meeting on Nuclear Research Applications and Utilization of Accelerators

4-8 May 2009, Vienna

AT/RD-06

In-Target Yields for RIB Production with EURISOL

J.C. David1, S.P. Chabod1,2, D. Doré1, D. Ene1, B. Rapp1,3, D. Ridikas1, and N. Thiollière1,4

1CEA-Saclay, IRFU/SPhN, Gif-sur-Yvette, France
2LPSC, Université Joseph Fourier Grenoble, CNRS/IN2P3, Institute Polytechnique de Grenoble, France
3CEA-Saclay, DRT/LIST/DETECS/LNHB, Gif-sur-Yvette, France
4SUBATECH, EMN-IN2P3/CNRS-Université, Nantes, France

Corresponding Author: jean-christophe.david@cea.fr

EURISOL DS (Europe Isotope Separation On-Line Design Study) project is the European common effort in planning a next generation RIB factory able to deliver secondary beams up to 1013 pps at energies up to 150 MeV u -1. The proposed schematic layout of the facility is based on four target stations, three direct targets of 100 kW of beam power and one multi-MW target two stages assembly.

Being produced via spallation the RIBs produced in the direct targets are mainly proton rich.
While in the multi-MW target high intensity RIBs of neutron rich isotopes are produced by fission in actinide targets placed in the fast neutron spectrum given by a liquid metal spallation source. The purpose of this paper is to summarize the work carried out within Task 11 “Beam Intensity Calculations” with special emphasis to the estimation of the in-target yield intensities produced in the various target configurations.

Benchmark studies were performed initially in order to verify the accurate description of the
spallation models used by the MCNPX2.5.0 code and to choose the best options to be used for the present work requirements. The predictions of the code tested against measured data are presented.

Several calculations using MCNPX2.5.0 combined with the evolution code CINDER’90 were carried out to assess the performance of the direct targets. A complex analysis was performed to study the in-target production RIB intensities varying with various parameters: target dimensions, materials and incident proton beam energies. The optimized configurations for the targets together with the corresponding quantitative estimates of the production rates for all interested nuclei resulted from this investigation are discussed.

The production rates in the case of the MMW-fission targets were obtained in two steps as follows.Fission rate energy distributions were firstly estimated with MCNPX2.5.0 using the geometry model previously optimized to reach 1015 fission s-1. Then individual production rates were further calculated based on the evaluated tables of yields for the fission products. Results for various fissile materials (235U (99.99%), 235U (20%), 235U (3%), Natural Uranium, Depleted Uranium and 232Th) are also presented.