OUR CONTRIBUTION INSIDE EURISOL TASK 11

1. Target parameters: • material (Al2O3, Pb…) • density (alloy, porosity…) • radius (0.9 cm to 2.55 cm) • length (8 cm to 125 cm) Spallation target • Beam parameters: • power • particle type (p, t, He…) • energy • gaussian parameter Incident beam (gaussian profile) • Nuclei of interest: • NuPECC : Ar, Be, Fe, Ga, • Kr, Ni, Sn • Additional: Hg, Li, Mg, • Ne, etc. On-line nuclei extraction Direct target OUR CONTRIBUTION INSIDE EURISOL TASK 11 • Simulations with multiple parameters • target parameters • beam parameters • Simulations with multiple parameters • target parameters • beam parameters • models and codes (MCNPX, CINDER, etc.) • Simulations with multiple parameters • target parameters • beam parameters • models and codes (MCNPX, CINDER, etc.) • many nuclei of interest • Simulations with multiple parameters • target parameters • beam parameters • models and codes (MCNPX, CINDER, etc.) • many nuclei of interest • Construction of an easy-access database for all simulated nuclei yields • Simulations with multiple parameters • target parameters • Simulations with multiple parameters OPTIMIZATION OF IN-TARGET NUCLEI YIELDS

2. BEST TARGET: Pb APPLICATION TO DIRECT TARGETS: 183Hg and11Be case • INPUT PARAMETERS • incident particle: proton • energy: 0.5 to 2 GeV • 3 targets: Pb, Ta, UCx • gaussian parameter: R/3 • code: MCNPX2.5 • model: INCL4/ABLA • contribution: n > 20 MeV •  preliminary results

3. BEST PROTON ENERGY AT CONSTANT POWER: 1 GeV 183Hg case (II)

4. Nuclei extraction efficiency decreases with volume  BEST LENGTH: 18 cm? 183Hg case (III) + 26 % + 64 % + 11 % + 50 %

5. 183Hg case (IV)

6. BEST TARGET: ? APPLICATION TO DIRECT TARGETS: 11Be case Si component O component • INPUT PARAMETERS • incident particle: proton • 3 targets: Al2O3, SiC, UCx • energy: 0.5 to 2 GeV • gaussian parameter: R/3 • code: MCNPX2.5 • model: INCL4/ABLA • contribution: n > 20 MeV •  preliminary results Al component C component

7. BEST TARGET: Al2O3 11Be case (II)

8. BEST PROTON ENERGY AT CONSTANT POWER: 1 GeV 11Be case (III)

9. Nuclei extraction efficiency decreases with volume  BEST LENGTH: 75 cm? 11Be case (IV)

10. 11Be case (V)

11. SUMMARY & OUTLOOK • Development of a methodology for in-target yields optimization •  MCNPX/CINDER simulations •  progressive construction of a database for simulated nuclei yields • Implementation of simple analysis programs for a fast navigation into the database content •  use of the database for target design optimization (examples of 183Hg or 11Be) • Extension of the methodology to additional direct targets (ex: Nb) and two- • staged (fission) targets • Relevance of simulation results is conditioned by the relevance of • spallation models (especially for light targets) and completeness of • cross section libraries • Final steps towards target designoptimization will require ion extraction • efficiencies

12. Outlook (continued) a) we contributed already in the double stage target for 6He beam production, namely p+W-->xn+Be. This work was already reported. b) we made some preliminary calculations on an alternative production of fission fragments using solid target-converter, namely p+Wxn+UCx. One could also try to work on d+Li,Be  xn+UCx. c) we did some calculation also in the case of presently « reference » MMW target p+Hgxn+U235, U238, and Th232 resulting in in-target fission yield distributions. We have the numbers and should report on that by the end of this year. d) Today there is a new design of the MMW target station based on MAFF concept. As our last contribution we will provide in this case different yields from p+Hgxn + various targets (U235, U238, Th232, and BeO). This we will be able to report early next spring. S. Chabod will leave CEA Saclay on 1 October  we look for another PostDoc candidate to continue this work!