Antonio C.C. Villari - GANILMoriond-2003 Radioactive beam research notches up 50 years Otto Kofoed-Hansen and Karl Ove Nielsen were the authors of NBI's first experiment (using ISOL technique). Their basic intent was to measure the recoil momentum resulting from the emission of a neutrino in beta decay. The best way to do this is with noble gas atoms, so Kofoed-Hansen and Nielsen set out to collect neutron-rich krypton isotopes produced in the fission of uranium. Author: Karsten Riisager The annual group photo for the Copenhagen theoretical physics institute

Antonio C.C. Villari - GANILMoriond-2003 This exercise is done for the selected cases and for low-intermediate energies Antonio C.C. Villari GANIL ISOL introduction and two examples: 18 Ne and 6 He

Antonio C.C. Villari - GANILMoriond-2003 N = .N i.N t.  NiNi targetIS separator N Accelerator = C. . I. R. 

Antonio C.C. Villari - GANILMoriond-2003 N = .N i.N t.  = C. . I. R.  Disadvantage of lower energies: R Advantages of lower energies:  and (  )

Antonio C.C. Villari - GANILMoriond-2003 Cross sections: Production of 18 Ne via 20 Ne + C at 100A MeV : 2.3 mb Production of 18 Ne via p+ 24 Mg at 1 GeV : 0.7 mb N target = for 1pµA beam . I. R.  BUT: Range of 20 Ne on C : 1740 mg/cm 2 Range of p on MgO : 390,000 mg/cm 2 . I. R.  You can increase the production by 60% in using MgO target

Antonio C.C. Villari - GANILMoriond-2003 Ar I max today ( 20 Ne) ~ 100 pµA N target = ( 18 Ne) . I. R. 

Antonio C.C. Villari - GANILMoriond-2003 . I. R.  Total beam power: 200kW 88%12% “Production” : 176kW “Diffusion” : 24kW 20 Ne 18 Ne < 2 cm

Antonio C.C. Villari - GANILMoriond-2003 Yield as a function of energy In 1 st approach: equal for any case. . I. R. 

Antonio C.C. Villari - GANILMoriond-2003 J. Obert Diffusion target for 6kW of primary beam power The total size is not optimised, in this case, for 20 Ne beam For 24kW, the total radiating surface should be multiplied by ~4  ~ 12 cm . I. R. 

Antonio C.C. Villari - GANILMoriond-2003 . I. R.  Cross section: Production of 6 He via 7 Li + C at 100A MeV : 8.0 mb Yield for 1pµA of 7 Li: Present intensity for 7 Li ~ 300pµA Therefore, possible yield: pps with 7 Li 100A MeV and pps with 7 Li target

Antonio C.C. Villari - GANILMoriond Li 6 He . I. R.  Total beam power: 210kW 100% Total decoupling of production and diffusion ( ) < 3cm

Antonio C.C. Villari - GANILMoriond-2003

Antonio C.C. Villari - GANILMoriond-2003 Measured at SIRa 6 He on POCO graphite (1µ) . I. R. 

Antonio C.C. Villari - GANILMoriond-2003 . I. R.  For 18 Ne: 80%

Antonio C.C. Villari - GANILMoriond-2003 . I. R.  Extremely dependent on the geometry. The smaller target the better efficiency. For 1s lifetime (1.7s and 0.8s) ~ 100% should be achievable.

Antonio C.C. Villari - GANILMoriond-2003 Permanent magnets, 10 GHz Running Online He(1+)~60% Ne(1+)~60% Ne(5+)~14% . I. R. 

Antonio C.C. Villari - GANILMoriond He100% 60%P.S. 18 Ne80%100%60%P.S. Diff. Eff. Ion C.B. The efficiency up to the C.B. can be of the order of 50% . I. R. 

Antonio C.C. Villari - GANILMoriond Ne 100A MeV 18 Ne Li 100A MeV 6 He Conservative version: On targetIn C.B. This is supposing a 300MV HI driver . I. R.  Gains: Li “converter”, Energy (X 10 for 450A MeV) and I… X 1.5 X 1.6

Antonio C.C. Villari - GANILMoriond-2003 The reaction 9 Be(n,  ) 6 He is being discussed in this session. Production of neutrons using “SPIRAL2” approach: 5mA Deuterons 40MeV on C X M.G. Saint-Laurent

Antonio C.C. Villari - GANILMoriond-2003 In order to produce in target, the thickness of Be corresponds to 100g/cm 2 (55 cm). NO ATTENUATION Conclusion 2: D 40MeV 5mA on C + Be (55cm) ~ pps of 6 He

Antonio C.C. Villari - GANILMoriond-2003 Very high efficiencies of light ions (particularly noble gases) can be achieved in ISOL. The requested yields of 6 He and 18 Ne requested for ß-beams “seem feasible” using standard solutions with projectile fragmentation. Solutions using very low beam energies (with high beam currents) look promising and should be better investigated.