1. Page 1NANUF03 - Bucharest - September 7-12 2003 Optimisation of UCx targets for fission induced by fast neutrons or electrons. Optimisation of UCx targets for fission induced by fast neutrons or electrons. Application for the SPIRAL 2 project and the ALTO project O. Bajeat a), S. Essabaa a), JM. Gautier e), Y. Huguet b), F. Ibrahim a), P. Jardin b), C. Lau a), N. Lecesne b), R. Leroy b), F.Nizery, c), M.Mirea d), F. Pellemoine b), A. Plukis c), D. Ridikas c) MG. Saint-Laurent b), ACC Villari b) a) Institut de Physique Nucleaire, 91406 Orsay, France b) GANIL, Bd H. Becquerel 14076 Caen cedex 5, France c) DAPNIA, CEA Saclay, 91191 Gif sur Yvette, France d) NIPNE, P.O. Box, MG-6, Bucarest, Romania e) LPC, 6, boulevard du Maréchal Juin, 14050 Caen Cedex, France Olivier BAJEAT

2. Page 2NANUF03 - Bucharest - September 7-12 2003 UCx Target by ISOLDE method UO 2 + 6C  UC + 2C0  + 3C  UC 2 + 2C0  + 2C The 3 steps of the manufacturing -Mixing powder precursors UO 2 (~ 20  m) and C (44  m) -Compressing the pellets ~ 8 tons/cm 2 -Carburation Heating under vacuum up to 2000 °C Pellets diameter 14 mm

3. Page 3NANUF03 - Bucharest - September 7-12 2003 Experimental results with the two ways Comparison with experiments Performed with the same Conditions using deuterons 20, 26, 50, 80 et 130 MeV Photo-fission at CERN a) electrons b) neutrons

4. Page 4NANUF03 - Bucharest - September 7-12 2003 Experimental results with the two ways Xe Kr ~ 4 Comparison of rare gas production with fast neutrons and photofission Ref.: F. Ibrahim et al. Photofission for the production of radioactive beams: experimental data from on-line measurement. European Physical Journal A 15, 2002, pp. 357-360

5. Page 5NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2 SPIRAL 2 : fast neutrons 40 MeV deuterons / 5 mA on C converter => 10 13 fissions/s Technical studies in progress until end 2004 2008 at GANIL (Caen)

6. Page 6NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2

7. Page 7NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2 project: the target-ion source system 0,2m 1,4 m 1m 0,75m 0,32m 2,25 m Primary beam Secondary beam

8. Page 8NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2: the FICNER code  mean = 1.25 barns Ref.: M. Mirea et al. Modeling a neutron rich nuclei source. European Physical Journal A 11, 2001, pp. 59-78 1 d --> 0.02 n

9. Page 9NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2: the target size Distance converter-target Diameter and length

10. Page 10NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2: the target shape What about a conical shape ? 1.7 10 13 f/s 1.6 10 13 f/s 1.6 10 13 f/s

11. Page 11NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2: two possible targets Target 2 Target 1

12. Page 12NANUF03 - Bucharest - September 7-12 2003 194 MeV per fission  300 W for 10 13 fissions/s SPIRAL 2: thermal aspect

13. Page 13NANUF03 - Bucharest - September 7-12 2003 SPIRAL 2: the oven graphite container reflectors support Electrical connections oven insulators Cooled chamber

14. Page 14NANUF03 - Bucharest - September 7-12 2003ALTO ALTO : photofission 50 MeV electrons / 10 µA => 10 11 fissions/s under construction operational in 2005 at IPN Orsay

15. Page 15NANUF03 - Bucharest - September 7-12 2003 Photofission: the FICEL code Electrons slowing down Photon production folding angular electron spread and bremsstrhalung differential cross section F de teta Ref.: M. Mirea et al. Exploratory analysis of a neutron-rich nuclei source based on photo-fission Nuclear Instruments and Methods in Physics Research B 201, 2003, pp. 433-448 θ

16. Page 16NANUF03 - Bucharest - September 7-12 2003 ALTO: the FICEL code Photon production

17. Page 17NANUF03 - Bucharest - September 7-12 2003 Photofission: the FICEL code θ Geant dipolar resonance

18. Page 18NANUF03 - Bucharest - September 7-12 2003 ALTO: the target production

19. Page 19NANUF03 - Bucharest - September 7-12 2003 ALTO: the shape of the target

20. Page 20NANUF03 - Bucharest - September 7-12 2003 ALTO: energy deposition 350 watt in the target

21. Page 21NANUF03 - Bucharest - September 7-12 2003 ALTO: target with converter

22. Page 22NANUF03 - Bucharest - September 7-12 2003 Release times (SPIRAL 2 and ALTO) MCNPX model for effusion study exact geometry description E c = 3/2 kT, T=2000°C source with cosine distribution on the surface

23. Page 23NANUF03 - Bucharest - September 7-12 2003 Release time (SPIRAL 2 and ALTO) Which space between pellets ? (Preliminary results) --> Large space isn’t necessary

24. Page 24NANUF03 - Bucharest - September 7-12 2003 ALTO: Accélérateur Linéaire Auprès du Tandem d’Orsay Section Beam stop Target / ion source PARRNe Separator Experiments with electrons Klystron

25. Page 25NANUF03 - Bucharest - September 7-12 2003 ALTO: specifications 50 MeV / 10 µA electron beam connected to the PARRNE 2 set up (used with 25 MeV / 1 µA deuton) fission yields × 100 5 photofission experiments of 3 weeks of irradiation per year Industrial applications Exploitation from 2005 Budget: about 1M € Accelerating section from CERN (LEP injector) RF equipment from LAL (Orsay)

26. Page 26NANUF03 - Bucharest - September 7-12 2003 ALTO: implantation

27. Page 27NANUF03 - Bucharest - September 7-12 2003 ALTO Accelerating section (from CERN) Target / ion source Quads Buncher

28. Page 28NANUF03 - Bucharest - September 7-12 2003 ALTO: characteristics Beam stopper Accelerating section Beam stopper E-gun Pre-buncher Buncher screen MI UMA Beam profiler WCM Magnet PARRNe target Frequency : 2,99855 GHz Repetition rate: 100 Hz max Energy : 50 MeV max Impulsion current duration: 2ns to 2µs Mean current max : 10 µA Maximum emittance: 6  mm.mrad at 50 MeV

29. Page 29NANUF03 - Bucharest - September 7-12 2003 ALTO: the target-ion source Ion sources: MK5, surface ionisation, laser...

30. Page 30NANUF03 - Bucharest - September 7-12 2003 ALTO: other applications Biochemistry Industrial applications Biochemistry under ionizing radiation Irradiation of proteins Study of DNA under radiation Study of electronic components under irradiation