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Advances in radioactive ion beam R&D at GANIL. P. Delahaye, GANIL. Talk overview. Radioactive accelerated beams at GANIL Present performances of SPIRAL Metallic ions beams SPIRAL FEBIAD beams SPIRAL 2 Laser ion source Charge breeding : The EMILIE project
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Advances in radioactive ion beam R&D at GANIL P. Delahaye, GANIL
Talk overview • Radioactive acceleratedbeamsat GANIL • Present performances of SPIRAL • Metallic ions beams • SPIRAL FEBIAD beams • SPIRAL 2 Laser ion source • Charge breeding: The EMILIE project • collaborative efforts towards EURISOL
3 kW 1,5 kW Radioactive acceleratedbeams Present GANIL facility Targets Production cave LIRAT A. Prost driving kart in the early 1970’s CIME Post-acceleration Of radioactive ions CIME: « Cyclotron d’ions de moyenne énergie » He Up to 20 AMeV CSS2 CSS1 Acceleration Stable ions Heavy ion sources Ne, Ar, Kr, N, O, F Heavy ion fragmentation on graphite targets 12C to 78Kr up to 95AMeV
REX-ISOLDE commemoration • What REX-ISOLDE isNOT • REX does not use an ECR ion source • It almostdidconsiderit! (2003-2008) • SPIRAL @ GANIL alreadydoes and will! • REX does not use a CW post-accelerator • But a pulsed LINAC • SPIRAL and SPIRAL2 @ GANIL (will) do! • HIE-ISOLDE might use a CW LINAC too! Comparison of charge breeding techniques during FP6
Cold transfertube He, N, O, F, Ne, Ar, Kr ECR multi-ionization in Nanogan 3 • Better ionisation efficiencies for gases! Highlyselective!! A. C. Villari et al., Nuclear Physics A 787 (2007) 126c–133c To the cost of universality
Post-acceleration in CIME • The cyclotron has an intrisichigh mass resolving power • R=m/dm usually5 103 to 104 • It is a CW machine • It goes up to 20AMeV! With the correct A/q • BUT complicated injection: 30% efficiency CIME workingdiagram
The past… and the future!Metallicbeams: a ‘hot topic’ for SPIRAL • Metallic (+ halogen + non metallic) elements • effusion times from ISOL targets are usually a penalty compared to rare gases • High ionizationefficienciesrequirededicateddevelopments (FEBIAD or RILIS), whereas for rare gasesalmostany ECRIS can do the job • N+ beams for post-acceleration • SPIRAL concept: 0 to n+ ionizationefficiencies are veryhigh for rare gases • BUT application to metallicbeams not straightforward as ECRIS are cold wall sources • 1+ n+ (=charge breeding) worksfairlywellwith EBIS but pulsedbeams (not suited to GANIL experiments) • 1+ n+ with ECRIS workswell in CW evenwithhighintensities but severalweaknesses: • Comparablylower charge states • Beampurity not guaranted • Lowefficiencieswith light metallicbeams: <5% up to K
Metallic ion beams • Metallicbeams @ SPIRAL
1+ N+ solution Present system 0 to n+ transformation Cold surfaces Onlygaseouselements 1+ to n+ transformation FEBIAD: 1+ beamsfrom condensable elementswithTfusion<2000°C Phoenix ECRIS: 1+ to n+ transformation FEBIAD ISOLDE M. Marie Jeanne, PhD thesis , UJF Grenoble, 2009
FEBIAD source: VADIS from CERN Goal: first ionization of gases and condensable elements Technicalrequirement: Target and ion source surfaces T(K)>~2300 Coupling to the SPIRAL target Thermal Calculations FEBIAD + SPIRAL 1 target F. Pellemoine and C. Bathe-Dejean, O. Bajeat L. Penescu et al., Rev. Sci. Instrum. 81(2010)02A906 ISOLDE – GANIL MoU
Tests in SIRa • in May with58Ni@ 75 AMeV • in July with36Ar @95AMeV + Latest tests SPIRAL Target Twobeam times withslight changes 1st test beam time Ta transfer tube wascutbecause of mechanicalconstraints, and finallymelted down! Metallicbeamsfrom a FEBIAD ion source FEBIAD ISOLDE Transfer tube broke down during the first tests
Tests in SIRa • in May with58Ni@ 75 AMeV • in July with36Ar @95AMeV + Latest tests SPIRAL Target Twobeam times withslight changes Bellow (IPNO design) 2nd test beam time Metallicbeamsfrom a FEBIAD ion source FEBIAD ISOLDE Transfer tube wasreplaced by a new including a bellow Source isstillworking, lack of conditionning made lowefficienciesduring the beam time
Deduced 1+ intensities 1st test PRELIMINARY 58Ni@75AMeV From Gamma line intensitiesat saturation Mostly >105pps! Despite the reliability and temperatures issues, the target ion source exhibits performances as good as one couldwish! Contains: Release efficiency(diffusion + effusion delays) Ionisation efficiency
Deduced 1+ intensities 2nd test PRELIMINARY 36Ar@95AMeV From Gamma line intensitiesat saturation taken on line • Ionisation efficiency ~10% of the nominal • lack of conditioning time • misbehaving extraction optics • Monitoredwith20Ne and verifiedwith35Ar (radioactive)
New elements to come… • Alreadymore beamsthanpresentlydeliveredat SPIRAL! • Most beams have projectedintensities > 106pps for 1.5kW primarybeam power Ionized as stable beams Ionised as radioactive beams Existingbeamsat SPIRAL Main milestones ● First 1+ beams ● First post-accelerated beams New beamsfrom FEBIAD (LIRAT, IBE): 2013 New beamsfrom Booster (CIME energies): end of 2014
Outlook:b-n angularcorrelationsat LIRAT • A wide program of measurements • Up to 10 Tz=1/2 emittersavailablewithrequiredintensities (>107pps) • Vud values frommirror nuclides • New candidates for other types of measurements • Exoticcurrents in beta decay • Mass selection: MR-TOF spectrometer Support fromUniversity Greifswald (R. Wolf and L. Schweikhard) for developing a MR-TOF-MS for LIRAT Design values: Mass resolving power >10000 Space charge capacity > 104 ions per bunch First simulations N. Bidault (RIKEN MR-TOF-MS)
Metallic ion beams • Metallicbeams @ SPIRAL 2
The SPIRAL 2 construction DESIR • Figures SPIRAL 2 phase 1 SPIRAL 2 phase 2 GANIL
SPIRAL2 facility RI produced by fission process, fusion evaporation residues or transfer products High intensity stable primary beams : P, D, 3,4He, heavy ions with A/Q=3 (1mA-5mA) Energy range : from 2MeV/u up to 20MeV/u (D), 14.5MeV/u (HI), 33MeV (P)
computer control 10 kHz Nd:YAG Pump laser 100 W wave - meter Ti:Sa 3 Ti:Sa 2 n x 2 Ti:Sa 1 n x 3 Latest news from the laser ion source GANIL Ion Source usingElectron Laser Excitation GISELE Laser system N. Lecesne, O. Bajeat, B. Osmond, M. Sjödin 3 TiSa cavities from TRIUMF 2 Tripler cavities from Mainz U. TiSa lasers: 200 – 500n & 700 – 1000nm
First laser ionization • TiSa laser, 20m transport path and hot cavity July 2011 • First Ga+ ion beam (+ Mainz U.) in July 2011 • Target and Ion Source for SPIRAL2: UCx + RILIS • Next beams: Sn, Zn, Y, In • N. Lecesne, Proceedings of the ICIS 2011 conf. to appear in RSI
The EMILIE project « Enhanced Multi-Ionization of short Lived Isotopes for EURISOL » Charge breeding for ISOL facilities P. Delahaye, A. Galata, J. Angot, G. Ban, L. Celona, J. Choinski, P. Gmaj, A. Jakubowski, P. Jardin, T. Kalvas, H. Koivisto, V. Kolhinen, T. Lamy, D. Lunney, L. Maunoury, A. M. Porcellato, G. F. Prete, O. Steckiewicz, P. Sortais, T. Thuillier, O. Tarvainen, E. Traykov, F. Varenne, and F. Wenander
Accelerator ISOL target 1+ ion source 1+ n+ 1+ separator A/q separator Charge breedingstudiesduring FP6 • Matching the A/q acceptance of the post-accelerator • Higher charge states corresponds to more compact post-accelerator and / or higher energies ECRIS and EBIS werecompared Advantages and drawbacks wereidentified 1+ N+: P. Delahaye et al., Eur. Phys. J. A 46(2010)421
Charge breeding techniques comparison • 132Sn > 1013 ions/s • ECRISbest suited: • Not space charge limited • CW device • 136Sn ~ 105 ions/s • EBIS best suited • Higher charge states • Higher purity Phoenix ECRIS Test stand at LPSC and ISOLDE REX-EBIS Operational at REX-ISOLDE Efficiency 1-20% depending on Z
Suggestion made for EURISOL P. Delahaye, O. Kester, C. Barton, T. Lamy, M. Marie-Jeanne, F. Wenander Eur. Phys. J. A 46(2010)421 NSCL - like CW EBIS charge breeder Lessdead time, piling-up and fakecoincidenceproblems REX-EBIS and MINIBALL: data acquisition problemswithintensities as low as 105-106pps CW beams! P. Delahaye, EMILIE Kick - off meeting
WP2Concept of CW EBIS charge breeder Post-accelerated beams for SPIRAL 2 Baseline scenario: Phoenix ECR charge breeder from LPSC Limitation in energy, especially for the second fission bump 132Sn Not favourable for transferexperiments!! Solution: EBIS + buffer trap = CW EBIS ISCOOL like RF trap REX-EBIS 132Sn33+isfeasible! (138-144Xe34+alreadydone) No intensitydecrease Up to 15 AMeV + Pulseddevice (10-500ms pulses)
WP3Improvement of the Phoenix ECR charge breeder performances Example: FP6 studywith a Phoenix ECRIS 14GHz, testedat CERN P. Delahaye and M. Marie-Jeanne, NIMB 266 (2008) 4429 PhD M. Marie-Jeanne, Université Joseph Fourier, 2009 Optimizing injection for light masses ISOLDE test stand Daresbury ECRIS ISOLDE test stand Daresbury ECRIS Optimizing injection for metallic ions Given by CCLRC to GANIL (Feb. 2010) Given by CCLRC to GANIL (Feb. 2010) SIMION SIMION Phoenix ECRIS T. Lamy, J. Angot and T. Thuillier, Rev. Sci. Instrum., 79 0A2909 (2008) and ref. therein.
SPIRAL:Phoenix charge breeder upgrade and installation Remotecontrolled injection tube Modified HF injection UHV design GANIL L. Maunoury C. Feierstein E. Traykov P. Delahaye ANL R. Vondrasek LPSC T. Lamy Latest tests at ANL: up to 9.6% Na8+ and 17.7% for K10+
Conclusion • Metallicbeams are a ‘hot’ topic for GANIL • New radioactive beamsfrom the ISOLDE VADIS at SPIRAL • First laser ionized stable beams for SPIRAL 2 • Charge breeding R&D isgoing on • Phoenix on-line at SPIRAL • Collaborative R&D for EURISOL within EMILIE
Outlook GANIL - SPIRAL 2 as a multi-user facility Fusion – evaporation (S3 and thick targets) SPIRAL 1 • Nb target fragmentation: in targetyieldsfrom 5E5 pps (74Rb) to 2E7pps (58Cu) “Other beams from other targets” (SPIRAL 2) 6He (BeO), 140(C), 29P, 30,31S (SiC) etc SPIRAL 2: N - induced fission 238U MG Saint Laurent et al, EXON 2009 AIP conf proceedings 40MeV d on 12C converter; HD UCx target SPIRAL 1
Thanks a lot for your attention And thanks a lot to mycolleagues O. Bajeat C. Couratin LPC Caen / GANIL (PhDThesis) M. Dubois P. Delahaye H. Franberg - Delahaye P. Jardin N. Lecesne L. Maunoury B. Osmond M. G. St Laurent M. Sjödin J. C. Thomas E. Traykov T. Stora F. Wenander L. Penescu E. Lienard D. Durand R. Vondrasek T. Lamy GANISOL ISOL beams for GANIL