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– collaborative efforts towards EURISOL

ISOL @ GANIL: SPIRAL

Radioactive accelerated beams

A. Prost driving kart in the early 1970’s

Heavy ion sources

CSS1

CSS2

Production cave

CIME

Acceleration Stable ions

Post-accelerationOf radioactive ions

Heavy ion fragmentation on graphite targets

Present GANIL facility

12C to 78Kr up to 95AMeV

LIRAT

3 kW

1,5 kW

Ne, Ar, Kr, N, O, F

He

Targets

Up to 20 AMeV

CIME:« Cyclotron d’ions de moyenne énergie »

REX-ISOLDE commemoration• What REX-ISOLDE is NOT

– REX does not use an ECR ion source• It almost did consider it! (2003-2008)

• SPIRAL @ GANIL already does 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!

Design Study Comparison of charge breeding techniques during FP6

ECR multi-ionization in Nanogan 3

• Better ionisation efficiencies for gases!

To the cost of universality

3 kW Graphite TargetRectangular wave guide

Insulators

Nanogan III 10GHz ECR ion source

Insulator

Plasma chamber

UHF Tunable cavitywith piston

0 V- 650 V

Polarized coaxial copper tube

3,3kW primary beam

Radioactive beam

Cold transfer tubeHe, N, O, F, Ne, Ar, Kr A. C. Villari et al., Nuclear Physics A 787 (2007)

126c–133c

Highly selective!!

• The cyclotron has an intrisic high mass resolving power– R=m/dm usually 5 103 to 104

– It is a CW machine– It goes up to 20AMeV! With the correct A/q

– BUT complicated injection: 30% efficiency

Post-acceleration in CIME

CIME working diagram

The past… and the future! Metallic beams: a ‘hot topic’ for SPIRAL

• Metallic (+ halogen + non metallic) elements– effusion times from ISOL targets are usually a penalty compared to rare gases– High ionization efficiencies require dedicated developments (FEBIAD or RILIS),

whereas for rare gases almost any ECRIS can do the job• N+ beams for post-acceleration

– SPIRAL concept: 0 to n+ ionization efficiencies are very high for rare gases– BUT application to metallic beams not straightforward as ECRIS are cold wall

sources– 1+ n+ (=charge breeding) works fairly well with EBIS but pulsed beams (not

suited to GANIL experiments)– 1+ n+ with ECRIS works well in CW even with high intensities but several

weaknesses: • Comparably lower charge states• Beam purity not guaranted• Low efficiencies with light metallic beams: <5% up to K

Metallic ion beams

• Metallic beams @ SPIRAL

1+ N+ solution

M. Marie Jeanne, PhD thesis , UJF Grenoble, 2009

1+ to n+ transformationFEBIAD: 1+ beams from condensable elements with Tfusion<2000°CPhoenix ECRIS: 1+ to n+ transformation

FEBIAD ISOLDE

Present system

0 to n+ transformationCold surfacesOnly gaseous elements

FEBIAD source: VADIS from CERNGoal: first ionization of gases and condensable elements Technical requirement: Target and ion source surfaces T(K)>~2300

L. Penescu et al., Rev. Sci. Instrum. 81(2010)02A906

ISOLDE – GANIL MoU

Thermal Calculations FEBIAD + SPIRAL 1 target

F. Pellemoine and C. Bathe-Dejean, O. Bajeat

Coupling to the SPIRAL target

Latest testsMetallic beams from a FEBIAD ion source

FEBIAD ISOLDE

Tests in SIRa • in May with 58Ni@ 75 AMeV• in July with 36Ar @95AMeV

+

SPIRAL TargetTwo beam times with slight changes

Transfer tube broke down during the first tests

Ta transfer tube was cut because of mechanical constraints, and finally melted down!

1st test beam time

Latest testsMetallic beams from a FEBIAD ion source

FEBIAD ISOLDE

Tests in SIRa • in May with 58Ni@ 75 AMeV• in July with 36Ar @95AMeV

+

SPIRAL Target

2nd test beam time

Two beam times with slight changes

Bellow (IPNO design)

Transfer tube was replaced by a new including a bellow

Source is still working, lack of conditionning made low efficiencies during the beam time

Deduced 1+ intensities 1st test

ISOTOPE Half-life (s) Power (W)Measured 1+ intensity

1+ intensity (750W)

Efficiency/EPAX (%)

38K 456 4 3.8E+04 7.3E+06 2.08E+0138mK 0.923 4 - - 53Fe 510.6 34 6.6E+04 1.4E+06 1.07E+0053mFe 154.8 34 1.4E+04 3.0E+05 2.24E-0158Mn 3 37 5.7E+04 1.2E+06 58Cu 3.204 37 4.3E+03 9.0E+04 59Cu 81.5 38 7.3E+04 1.5E+06 60Cu 1422 35 2.5E+03 5.E+04

Mostly >105 pps!Contains:Release efficiency (diffusion + effusion delays)Ionisation efficiency

From Gamma line intensities at saturation

Despite the reliability and temperatures issues, the target ion source exhibits performances as good as one could wish!

58Ni@75AMeV

PRELIMINARY

Deduced 1+ intensities 2nd testFrom Gamma line intensities at saturation taken on line

ISOTOPE Half-life (s) Power (W)Measured 1+ intensity

1+ intensity (1.5kW) and nominal ionisation efficiency

23Mg 11.3s ~13 1.73E+03 2.00E+0625Al 7.18s ~13 2.60E+02 3.00E+0533Cl 2.5s ~13 6.93E+03 8.00E+0635Ar 1.775s ~13 8.67E+03 1.00E+0737K 1.226s ~13 1.10E+04 1.27E+0738K 6.3min ~13 1.30E+04 1.50E+07

38mK 923ms ~13 1.30E+04 1.50E+07

36Ar@95AMeV

Ionisation efficiency ~10% of the nominal• lack of conditioning time• misbehaving extraction opticsMonitored with 20Ne and verified with 35Ar (radioactive)

PRELIMINARY

•Already more beams than presently delivered at SPIRAL!

• Most beams have projected intensities > 106 pps for 1.5kW primary beam power

Existing beams at SPIRAL

Ionised as radioactive beams

Ionized as stable beams

New beams from FEBIAD (LIRAT, IBE): 2013New beams from Booster (CIME energies): end of 2014

New elements to come…

Item 2011 2012 2013 2014

Nuclear ventilation ASN Installation

Production cave Modification

FEBIAD New prototype tests

Charge breeder Design, orders Upgrade Commissionning● First 1+ beams

●

First post-accelerated beams

Main milestones

Outlook: b-n angular correlations at LIRAT

• A wide program of measurements– Up to 10 Tz=1/2 emitters available with required intensities (>107pps)

• Vud values from mirror nuclides

– New candidates for other types of measurements• Exotic currents in beta decay

• Mass selection: MR-TOF spectrometer

Design values:Mass resolving power >10000Space charge capacity > 104 ions per bunch

First simulations N. Bidault(RIKEN MR-TOF-MS)

Support from University Greifswald (R. Wolf and L. Schweikhard) for developing a MR-TOF-MS for LIRAT

Metallic ion beams

• Metallic beams @ SPIRAL 2

The SPIRAL 2 construction

• FiguresSPIRAL 2 phase 1

GANIL

DESIR

SPIRAL 2 phase 2

SPIRAL2 facilityRI 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)

GISELE Laser systemGANIL Ion Source using Electron Laser ExcitationN. Lecesne, O. Bajeat, B. Osmond, M. Sjödin

3 TiSa cavities from TRIUMF

2 Tripler cavities from Mainz U.

computercontrol

n x 3

n x 2Ti:Sa 2

Ti:Sa 1

Ti:Sa 3

10 kHz Nd:YAGPump laser

100 W

wave -meter

TiSa lasers: 200 – 500n & 700 – 1000nm

Latest news from the laser ion source

TiSa laser, 20m transport path and hot cavity

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

739.15739.2739.25739.3739.35739.4739.45739.5

Rydberg state of Ga

3rd step (nm)

Ga +

(a.u

.)

July 2011

First laser ionization

Charge breeding

The EMILIE project

« Enhanced Multi-Ionization of short Lived Isotopes for EURISOL »

Charge breeding for ISOL facilities

Design Study

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

Charge breeding studies during FP6

ISOL target 1+ ion source

1+ n+1+ separator A/q separator

Accelerator

Design StudyECRIS and EBIS were comparedAdvantages and drawbacks were identified

1+ N+: P. Delahaye et al., Eur. Phys. J. A 46(2010)421

• Matching the A/q acceptance of the post-accelerator• Higher charge states corresponds to more compact post-accelerator and / or higher energies

Charge breeding techniques comparison

Efficiency 1-20% depending on Z

Design Study

Phoenix ECRIS Test stand at LPSC and ISOLDE

REX-EBISOperational at REX-ISOLDE

132Sn > 1013 ions/sECRIS best suited:• Not space charge limited• CW device

136Sn ~ 105 ions/sEBIS best suited-Higher charge states-Higher purity

P. Delahaye, EMILIE Kick - off meeting

Detail of the EURISOL LayoutModified from P. Butler’s presentation, NuPECC meeting June 2007

Low-resolutionmass-selector

To low-energy areas

BunchingRFQRFQs

Chargeselector

1+ beam from the target – ion source units

High intensity RFQ cooler

High-resolutionmass-selector

To low-energy areas

ECRIS Charge breeder

Cooler Buncher

EBIS“push-pull” mode

LINAC

SC cavities

HT

P. Delahaye, O. Kester, C. Barton, T. Lamy, M. Marie-Jeanne, F. Wenander Eur. Phys. J. A 46(2010)421

NSCL - like

CW beams!

Suggestion made for EURISOL

CW EBIS charge breederLess dead time, piling-up and fake coincidence problemsREX-EBIS and MINIBALL: data acquisition problems with intensities as low as 105-106 pps

WP2Concept of CW EBIS charge breeder

Post-accelerated beams for SPIRAL 2Baseline scenario: Phoenix ECR charge breeder from LPSCLimitation in energy, especially for the second fission bump

Charge state Energy (AMeV)

Intensity (pps)

18+ 5.0 1.8E7

25+ 9.6 1.8E6

132Sn

Solution: EBIS + buffer trap = CW EBIS

REX-EBIS132Sn33+ is feasible!(138-144Xe34+ already done)No intensity decreaseUp to 15 AMeVPulsed device (10-500ms pulses)

ISCOOL like RF trap

Not favourable for transfer experiments!!

+

WP3Improvement of the Phoenix ECR charge breeder performances

ISOLDE test stand Daresbury ECRIS

Given by CCLRC to GANIL (Feb. 2010)

P. Delahaye and M. Marie-Jeanne, NIMB 266 (2008) 4429PhD M. Marie-Jeanne, Université Joseph Fourier, 2009

SIMION

Optimizing injection for light masses

Example: FP6 study with a Phoenix ECRIS 14GHz, tested at CERN

ISOLDE test stand Daresbury ECRIS

Given by CCLRC to GANIL (Feb. 2010) SIMION

Optimizing injection for metallic ions

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

Remote controlled injection tubeModified HF injectionUHV design

GANILL. Maunoury C. Feierstein E. TraykovP. Delahaye

ANLR. Vondrasek

LPSCT. Lamy

Latest tests at ANL: up to 9.6% Na8+ and 17.7% for K10+

Conclusion

Conclusion• Metallic beams are a ‘hot’ topic for GANIL

– New radioactive beams from the ISOLDE VADIS at SPIRAL

– First laser ionized stable beams for SPIRAL 2• Charge breeding R&D is going on

– Phoenix on-line at SPIRAL– Collaborative R&D for EURISOL within EMILIE

MG Saint Laurent et al, EXON 2009 AIP conf proceedings

SPIRAL 2: N - induced fission 238U

“Other beams from other targets” (SPIRAL 2)6He (BeO), 140(C), 29P, 30,31S (SiC) etc

SPIRAL 1

SPIRAL 1

Fusion – evaporation(S3 and thick targets)

40MeV d on 12C converter; HD UCx target

Nb target fragmentation: in target yields from 5E5 pps (74Rb) to 2E7pps (58Cu)

Outlook

GANIL - SPIRAL 2 as a multi-user facility

Thanks a lot for your attention

E. Lienard D. Durand

O. BajeatC. Couratin LPC Caen / GANIL (PhD Thesis)M. DuboisP. DelahayeH. Franberg - DelahayeP. JardinN. LecesneL. MaunouryB. OsmondM. G. St LaurentM. SjödinJ. C. ThomasE. Traykov

GANISOLISOL beams for GANIL

T. StoraF. WenanderL. Penescu

T. Lamy R. Vondrasek

And thanks a lot to my colleagues