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Introduction

C. D. 1+. n+. UCx. IS. ECR. Introduction. To extend the study of the structure of nuclei far from stability

mickey
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Introduction

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  1. C D 1+ n+ UCx IS ECR Introduction To extend the study of the structure of nuclei far from stability • Production of RIB's via the fission process induced - either by fast neutrons from a C converter in a UCx target goal >1013 fissions/s - or by direct bombardment of fissile material • Production of heavy ion beams for fusion-evaporation physics Basic configuration for RIB production : high intensity D primary beam on a D-N Converter with a Carbon wheel fission fragments produced by N-induced fission of aUCx fissile target - low or high density (Gatchina) Different ion sources coupled (depending on ionization efficiency) Isotopes bred to higher charge state for proper post-acceleration Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  2. n d UCx d,3,4He,... UCx Fission yields with converter and ~ 5 mA primary beam... low density  = 2.3 g/cm3 1013 f/s V = 240 cm3 300 W high density  = 11 g/cm3 5.1013 f/s V = 240 cm3 2.1014 f/s V = 1000 cm36 kW (limit) Fission of 239UEx= 20 MeV 200 kW dissipation in the converter5 mA - 40 MeV deuteron power depositedin the target without converter and ~ 0.15 mA primary beam... 5.1012 f/s6 kW Fission of 240PuEx≥ 50 MeV acces to a wider mass region Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  3. Z N Regions of the nuclear chart covered by primary beam:  deuterons  heavy ions 4. N=Z ISOL (thick target) 5. Transfermiums In-flight (Z=106, 108) 2. Fusion reaction with exotic beam1 1. Fission products (w/ converter) 3. High Ex fission products (w/o converter) Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  4. Physics with fast neutrons Material irradiation SPIRAL2 will deliver  1015 neutrons /s peaked at 14 MeV ideal spectrum for material studies in future fusion machines available before IFMIF and at reduced cost Pulsed neutron beam (future option) measurement of cross-sections for fission and (n,xn) reactions neutron energy inferred from time of flight technique (ToF) with 1% resolution for 10 m long beamline Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  5. Schematic Layout RIB's  6 MeV/u Charge breeder 1+ / N+ RFQ α Source q/A=1/3 CIME Source deuterons Separator Direct beamlines G1/G2 SC LINAC TIS Station Identification station Beam dump Stable ion beams Low Energy exp. area potential extension Irradiation Neutrons 14 MeV • Driver • Target - Ion Source Station • Secondary Beam Lines • High Energy Radioactive Beam Lines Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  6. RIB's  6 MeV/u Charge breeder 1+ / N+ RFQ α Source q/A=1/3 CIME Source deuterons Direct beamlines G1/G2 SC LINAC Identification station Low Energy exp. area B. Bru : Séparateur F. Varenne : Lignes de faisceaux secondaires • Driver • Target - Ion Source Station • Secondary Beam Lines • High Energy Radioactive Beam Lines Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  7. Facility layout Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  8. Simultaneous beams at GANIL Multi-Faisceaux easier with direct linesCIME  salles G1-G2 séparateur 3 1+/n+ 1 4 5 2 Example (5 beams) SPIRAL2 : 40 MeV D+ onto ECS 1) Low energy RIB (LIRAT) 2) 6 A.MeV RIB CIME  VAMOS / EXOGAM Standard GANIL 3) stable beam/RIB at 50-100 A.MeV (CSS ’s) 4) 1 A.MeV stable (IRRSUD) 5) 8-10 A.MeV stable (SME) Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  9. Converter beam spot Ø 40 mm (parabolic distrib)thickness = 10 mmrotation speed < 600 trs/mn in case of C wheel failure : target protection = Carbon foil between wheel and target  70 ms to switch the beam off(time delay for 1000° to 3200°C increase) Homogeneous and Bragg model energy deposition Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  10. Targets Geometry of the UCx target has been studied by calculating the optimum location taking into account the distribution of the neutron flux coming from the converter. 3 geometries giving > 1013 fissions/s complete effusion simulations in progress R. Leroy : Production des ions radioactifs 19 series of 61 disks UC3density 2.3 g/cm3 Ø15, thickness = 1, spacing = 0.3 Example of configuration Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  11. Ion Sources • Four types of ion sources considered for the project : • ECR ion source (gaseous elements such as the noble gases) • FEBIAD source (Forced Electron Beam for Ionization by Arc Discharge)(less volatile elements) • thermo-ionisation source (alkalis and some rare earth elements) • laser source (non-volatile elements such as metallic ones and high selectivity) • prototype of ECR ion source (demanding in terms of room & auxiliary equipment) • adaptation of the surface ionisation source developed at TRIUMF • development of a FEBIAD prototype for pushing up the usual lifetime limitation Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  12. Plugs Adaptation of the plug technology developed at TRIUMF Shielding of all radio-sensitive elements, like pumps (32 Sv/h at 1 m after 3 month irradiation)) Manual disconnection of the module before handling for storing or dismantling Size of biological shielding determined by dose rate calculations < 10 μSv/h at the top) (basic, complete, in the vacuum tank) Service cap Shielding plug 1.25 m steel + 1.50 m concrete Containment Box D-beam axis RIB axis Shutter Valve Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  13. Plugs (2) couvercle béton passages avec câble HT ECS Plugs Basse Energie Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  14. Driver • The driver must accelerate beams • of high power (200 kW deuteron beam power) • different ion species and mass-to-charge ratios (deuterons as well as heavier ions of mass-to-charge ratio A/q=3 and up to A/q=6 in a later stage) • with a high output energy flexibility (from 40 MeV deuteron energy down to low energies, as low as the RFQ exit energy) • “Independently Phased Superconducting Linac” : provides a safe cw operation and high flexibility in the acceleration of different ion species and charge-to-mass ratios • Short cavities: very wide velocity acceptance  optimisation of the output energy for each ion specie by readjusting the RF phases of each cavity a) conservative  expected from sources b) z at RFQ output Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  15. RFQ 2 Driver layout : reference design 0 6 m 11 m 15 m 28 m 40 m 88 MHz =0.07 88 MHz =0.12 RFQ MEBT QWR (12 mod x 1 cav) Sources + LEBT QWR (6 mod x 2 cav) 88 MHz Source D+ RFQ 1 Eacc = 6-7 MV/m Source q/A=1/6 Source q/A=1/3 Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  16. Hexapolar magnet Monogap extraction Water cooling UHF injection Gas injection Plasma electrode Hybrid magnet for Hexapolar and Axial field Magnet for axial field D+ sources: SILHI-type & μPhoenix ex: MicroPHOENIX 10 GHz norm. rms  = 0.084 .mm.mradfor 5 mAe D+ extracted @ 38 kV Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  17. Heavy Ions Sources R&D • A/q=3 ion source : • state-of-the-art in ECR sources: 1 mA 18O6+ and 0.2 mA 36Ar12+ • High confinement fields (Br  2-3 T) and high frequency (f > 28 GHz) required •  Two options are explored, based on • a fully superconducting ECR source • a combination of permanent and high temperature superconducting magnets • European research activity “Ion Sources for Intense Beams of Heavy Ions” (ISIBHI) P. Sortais & D. Hitz : sources ECR SERSE at LNS 14-18 GHz PHOENIX 28 GHz Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  18. Beam Dynamics (2) 1/3 cavity aperture Results : • suitable emittance growths • safety margin [bore radius / max beam amplitude] 1.8 for ions 2.5 for deuteron • next step : • systematic start-to-end simulations including all effects and alignment errors Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  19. Warm intertank space Quads + Diagnostics : trade-off between BD and Diag people ! Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  20. Accelerates in CW mode: D+ beam up to 5 mA up to 0.75 – 1 MeV/u q/A=1/3 ions up to 1 mA To allow hands on maintenance: 99% of transmission w/o errors 97% min with all combined errors The construction takes into account: Non constant voltage and R0profile  1% on the voltage law  1/10th mm vane tips displacement Minimum price 6.5 m 5 m RFQ Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  21. RFQ : 4-vane from tube and rf joints safe cw operation (lowest peak power density < 6W/cm2) highest transmission • Only mechanical assembly • from a low cost copper tube • Possible change of the vanes • w/o brazing nor welding  RF join Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  22. Resonators G. Devanz & G. Olry : Cavités supra SPIRAL2 Legnaro-typeQWR Argonne-type QWR and HWR(with field asymmetry compensation) Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  23. QWR : cavity shape optimization Goals for 8 MV/m (E/)operation :  lower Epk / Eacc ~ 5 → Epk ≈ 40 MV/m  enlarge curvature radius of drift tube  lower Bpk / Eacc ~ 10 mT/MV/m → Bpk ≈ 80 mT  enlarge stem diameter Cavity stiffening : Stem  conical shape Top  rounded shape Power coupler location : Coupler mounted on removable bottom plate Electric coupling in low |H| area  Qext as low as 7 104 50 ohms coaxial line Ø = 30 mm Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  24. R&D program (1) • Goal : to develop and test the most critical components to validate the chosen technology before the construction phase • Provisional budget for this 2-year R&D program = 850 k€ • For the accelerator : • One RFQ module (1 meter long)test at full RF power in summer 2004 with a 88 MHz-40 kW power source • Two 176 MHz SC resonators, one QWR + one HWRto validate fabrication, preparation and mounting proceduresto compare performances of both cavity types (tests before the end of 2004) • Two high power couplers (in the range 10-20 kW)fabrication at the end of 2004 and test in 2005. • One 10 kW solid state amplifier module for the SC resonatorscollaboration with other laboratories under studygoal : prototype tested at the end of 2004 Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  25. R&D program (2) • For the target-ion source system : • Target R&D already started within a collaboration with Gatchinagoal : to compare the performances of low and high density UCx targetsbesides, R&D on low density UCx pellets of different sizes and shapes • Design and developments of the target ovengraphite oven prototypes tested to study temperature uniformity and mechanical resistance for a long operation period • FEBIAD ion source tests to demonstrate the reliability of the cathode for a long period operation • ECR ion source tests to demonstrate the feasibility of a prototypeusing magnetic coils Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  26. Time-schedule for Safety Authorities Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  27. Accelerator Target stations Beam Lines Specific Techn. Conv. Facilities Safety Radiation D+ Sources Ion Sources RFQ Cryomodule A/B Beam Dynamics RF Cryogenics Integration Converter Targets Ion Sources Hot Cell Plug & Handling. Separator Calculs lignes Magnets CIME post-acc. Charge booster 1+/n+ Diagnostics Vaccum Control systems Buildings Elec. Power Power Supplies Refrig. / Fuides Waste Tech. Support • Studies • Safety • Rad. shielding • Documents Prep. • DOS, RPS, • DAM, DAR Project organization DSM Institutes IN2P3 Steering Committee TACTechnical Advisory Committee SACScientific Advisory Committee Project Study Group Project Management Nuclear physics, atomic, astrophysics .. Physics/Exp. Joint Laboratories Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

  28. Argonne UK ?? Louvain ?? Gatchina Triumf LPC GSI ?? SPR GANIL DAPNIA IRES DPII CSNSM IPNO Isolde ?? DIF ISN CENBG CENG Legnaro Collaborations Le projet SPIRAL-II, 5 octobre 2003, Porquerolles

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