1. P. Delahaye for the EMILIE collaboration
Optimizing charge breeding techniques for ISOL facilities in Europe: Conclusions from the EMILIE project
P. Delahaye for the EMILIE collaboration

2. World status: 2015 TRIUMF SPIRAL1&2 ISOLDE NSCL ReA3 ANL SPES RISP
ECRCB
ECRCBEBIS
ISOLDE
EBIS
NSCL ReA3
ANL
SPES
ECRCBEBIS
ECRCB
RISP
EBIS
EBIS
ECRCB + EBIS
Texas A&M
ECRCB
ANURIB
ECRCB + EBIS
ECRCB
In commissionning or planned
EBIS
running

3. Following the suggestion made for EURISOL
P. Delahaye, O. Kester, C. Barton, T. Lamy, M. Marie-Jeanne, F. Wenander Eur. Phys. J. A 46(2010)421
Intense beams
ECRIS challenges
Beam purity and capture efficiency optimizations

4. Following the suggestion made for EURISOL
P. Delahaye, O. Kester, C. Barton, T. Lamy, M. Marie-Jeanne, F. Wenander Eur. Phys. J. A 46(2010)421
High charge states
Dead time,
pile-up,
fake coincidences
REX-EBIS and MINIBALL: DAQ problems with intensities as low as
pps
EBIS beam debuncher motivations:
Less dead time, piling-up and fake coincidence problems which are presently caused by the EBIS pulses! 1ms every 50 – 500 ms.
REX-EBIS and MINIBALL: data acquisition problems with intensities as low as pps
EBIS debuncher: solving this problems with intensities from 10^5 up to 10^10pps (maximum EBIS capabilities)
EBIS challenges
For mid-term ISOL facilities time structure is the main issue (before space charge limitations)
Recall Stefan’s presentation

5. EMILIE objectives EBIS debuncher
Simulation, Construction and test of a novel concept of EBIS beam debuncher
Optimization of the performances of ECR charge breeders of Phoenix type
Gaining understanding in the 1+ n+ technique
Optimization of performances
First tests at LPC Caen
Optimization of the SPIRAL and SPES charge breeders
See Laurent Maunoury’s poster ThuPE31
See Alessio Galatà’s presentation and poster ThuPE26

6. EMILIE objectives EBIS debuncher
Simulation, Construction and test of a novel concept of EBIS beam debuncher
Optimization of the performances of ECR charge breeders of Phoenix type
Gaining understanding in the 1+ n+ technique
Optimization of performances

7. No buffer gas, UHV design
CW EBIS charge breeder
EBIS
Charge breeding
Mass separation
In trap decay CW
Buffer trap
Slow extraction
Pseudo CW
Linear RFQ trap
Using the energy spread
Dead time,
pile-up,
fake coincidences
REX-EBIS and MINIBALL: DAQ problems with intensities as low as
pps
RFQ cooler 1+ N+
Post acceleration
A/q or TOF
separation
CW injection or bunching in a RF trap
Pulsed
No buffer gas, UHV design
Entrance
electrode
Exit
electrode
DC for axial + RF for radial trapping
Injection
from EBIS CW
beam

8. Debuncher prototype design
Completed in 2012 at LPC
Y. Merrer
P. Desrues
Downscaled prototype from original trap
L: 0.5m  1m
P=10-8mbar  10-11mbar
RF rods
Entrance
electrodes
Exit
DC segments DC RF
Focusing
electrodes
R0 = 15 mm
RF rods Ø34.4 mm

9. Simulations with SIMION – results 2012
20 20 kV
E. Traykov
E [eV]
time [µs]
extraction
injection
Cool effect!
E [eV]
[counts]
extraction
injection
Transverse
emittance
increase
(FWHM)
Time flattening
average
[counts]
time [µs]
Typical settings:
URF = 400 V, fRF = 4 MHz, Tcycle = 8000 µs,
A/Q = 3.5, DE = 10.Q eV , DTOF = 50 µs.
Can be flattened further by
number/size of drawers, DC rise time, overlapping
>85 % efficiency for a 45 cm long debuncher
A higher energy spread would require
 longer debuncher
 stronger confinement

10. Tests bench mechanical adaptation
Adaptation flange
The first test of emilie debuncher will be made on the SHIRaC test bench, SHIRaC is a SPIRAL2 high intensity RFQ Cooler demonstrator. It is installed at LPC CAEN laboratory.
an adapter flange has been machined to adapt the emilie debuncher to the SHIRaC test bench
SPIRAL2 high intensity RFQ cooler demonstrator (SHIRaC) at LPC CAEN
Emilie debuncher on the adaptation flange
Emilie debuncher on the test bench
Jean-François CAM Colloque GANIL 2013

11. @ low power (< 10 Watts)
RF system
Production of RF voltages on the quadrupole
JF Cam
Principle of the production system RF
Vrf: 450V pic to 4MHz
Frequency range: 2MHz to 6 MHz
Voltage range: (pic to pic) : 0 to 1.2kV
@ low power (< 10 Watts)
Jean-François CAM Colloque GANIL 2013

12. Debunching voltage ramp generator
JF Cam
Goal: Produce 8 voltages ramps (few volts/ms to 100 v/ms)
Sequencer:
gate and delay
generator
8 channels voltage
Amplifier 500V
G=50 & BW=15KHz
2x4 channels AWG
LECROY ArbStudio
Wired splitter
8 -> 23 channels x2 11 12
optical
fiber
link
To sequence the generators and the lenses switches, we will use a multi-channel gate and delay generator. To produce the differents waveform for the voltage ramp, we will use 2 AWG and to obtain the necessary voltage amplitude we will use a 8 channels voltage amplifier. The ramping voltages will be distributed by a wired spliter. Because the debuncher will be install on the high voltage platform, it’s necessary to connect the computer to generators with an USB optical fiber link RF
Computer to set AWG generators
Ramping voltage exemple
Emilie quadrupole
Jean-François CAM Colloque GANIL 2013

13. Tests at LPC Caen
First tests with continuous beams of singly charged ions
Injected bunches defined by pulsing the injection electrode voltage
Segments are raised to debunch the beam DC DC
Focusing
electrodes
Focusing
electrodes RF
MCP or FC
Incoming beam
Kimball source: Na+ and Cs+ ions, 50nA , 5 keV
F1094
Hamamatsu
First extraction electrode
Last injection electrode
-1400V
MCP signal: linear with the incoming current

14. Results Transmission though the trap (no bunching): >90%
Trapping half-life: >100ms (Na+) > 1s (Cs+)
Injected Na+ bunches
baseline

15. Results Transmission though the trap (no bunching): >90%
Trapping half-life: >100ms (Na+) > 1s (Cs+)
Injected Na+ bunches
baseline

16. Extraction modes from REXEBIS
FWHM ~30 ms
FWHM ~400 ms
D. Voulot et al., NIM B 266 (2008) 4103
400 µs in every ms!
Typical EBIS
breeding
cycles
~30 to 50% efficiency
…to ~6ms
From ~400µs…

17. EMILIE debuncher: Summary and future plans
EMILIE debuncher status
EBIS debuncher has produced first results
6-7 ms pulse without much optimization
30% - 50% efficiency
Next steps
Further voltage and timing optimizations
Flattening the debunched beam
Better efficiencies
Observation of pulses over longer times (up to 100ms)
Data acquisition allowing the single ion detection
Defining the injected bunches with a pulsed deflector (removal of the overshoot)
Mimicking the EBIS pulses
Energy dispersion
Adding a RF voltage on top of the EBIS debuncher voltage
No effect for 7V, what happens for higher voltages
Future plans
Tests with multiply charged ions at GANIL in 2016
Possible tests with TWIN EBIS at ISOLDE
Within ENSAR 2!

18. EMILIE objectives EBIS debuncher
Simulation, Construction and test of a novel concept of EBIS beam debuncher
Optimization of the performances of ECR charge breeders of Phoenix type
Gaining understanding in the 1+ n+ technique
Optimization of performances

19. EMILIE objectives EBIS debuncher
Simulation, Construction and test of a novel concept of EBIS beam debuncher
Optimization of the performances of ECR charge breeders of Phoenix type
Gaining understanding in the 1+ n+ technique
Optimization of performances

20. Comparison of « standard » ECRIS and charge breeder performances
Comparison of performances for a 14GHz source and a 14 GHz charge breeder Phoenix at LPSC vs JYFL ECRIS
Same conclusions, despite lower magnetic field confinement and no bias disc in Phoenix
Double frequency heating  higher charge states, higher efficiencies
H. Koivisto et al, RSI 85 (2014)
Presented at ICIS 2013

21. 1+ beam capture probability
Charge breeding efficiency is determined by Capture efficiency of the 1+ beam Ionization efficiency from 1+ to n+ Extraction efficiency of the n+ ions Slowing down coefficient of the incident 1+ ions in ion-ion collisions R(uab) is at maximum when the incident ion velocity equals the average speed of the plasma ions Experiments with the Phoenix charge breeder at LPSC: breeding efficiency of high charge state ions as a function of incident velocity matches well with the prediction
O. Tarvainen et al., Plasma Sources Sci. Technol. 24, 3, (2015)
Delcroix and Bers 
Slowing down depends on the ratio of velocities (ISOL ion/ plasma ion)
Slowing down coefficient superimposed to the DV curve
Capture mechanism is qualitatively well understood

22. 1+ beam capture probability as a diagnostic tool of ECR plasmas
Low charge states extracted from the breeder behave differently Incident 1+ ions can propagate through the breeder plasma. This is confirmed by comparing their ’breeding time’ with the ion flight-time without plasma. 2+ is produced via in-flight ionization Measurement of the 1+ and 2+ ’breeding efficiencies’ yields an estimate for ion mean free path, ion-ion collision frequency and plasma density The incident 1+ beam is a perfect diagnostics tool for ECRIS plasmas! Experiments with Na, Rb, Cs have been carried out, showing similar results.
Fraction of 1+ / 2+ beams through the ECR plasma  mean free path
Ion – ion collision frequency
Q>3 ions are collisional ions
Q<~3 are magnetized ions
Electron density
~1 order of magnitude below the cut-off density
40kHz for 1+ ions
41011 e/cm3
O. Tarvainen et al., Plasma Sources Sci. Technol. 24, 3, (2015)

23. EMILIE objectives EBIS debuncher
Simulation, Construction and test of a novel concept of EBIS beam debuncher
Optimization of the performances of ECR charge breeders of Phoenix type
Gaining understanding in the 1+ n+ technique
Optimization of performances

24. Ionization of C beams at LPSC and GANIL
PREMAS task 3 +
Ionization of C beams at LPSC and GANIL
GANIL
Phoenix + LPSC
For Carbon beams direct multi-ionization in Nanogan is prefered compared to charge breeding in Phoenix
BUT: Phoenix possibly better for higher charge states and beam purity
GANIL
L. Maunoury et al, RSI 85 02A504 (2014)
Presented at ICIS 2013

25. Light ion charge breeding at ANL
Nov. 2011
Efficiencies for Na and K improved by a great amount
Playing with jaws to optimize efficiency
possible effect of the emittance of the 1+ beam?
R. Vondrasek, P. Delahaye, S. Kutsaev and L. Maunoury, Rev. Sci. Instr. 83(2012)113303
P. Delahaye, L. Maunoury, R. Vondrasek, Nucl. Instr. Meth. A, 693(2012)104.

26. Improvement of charge breeding efficiencies
1) Injection of molecules
2) Vaccuum improvement
Lower residual pressure
3) Magnetic field improvements:
symmetrization at injection
axial field optimization
4) Double frequency heating
40Ar8+
39K9+
40Ar8+
40Ar8+
39K9+
133Cs27+
LPSC charge breeder
ANL charge breeder
EMILIE
23Na8+
84Kr17+
39K9+
133Cs27+
23Na7+
85Rb19+
85Rb19+
85Rb19+
23Na7+
23Na7+
13C4+ (CO+)
13C4+
EMILIE 2015
SPIRAL charge breeder
SPES charge breeder
P. Delahaye, NIM B 317(2013) ,
J. Angot et al, THYO02, ECRIS 2012
H. Koivisto et al, RSI 85 (2014)
L. Maunoury et al, RSI 85 02A504 (2014)
T. Lamy et al, ECRIS 2014
Laurent Maunoury ThuPE31
Alessio Galatà ThuPE26

27. Charge breeding times

28. EMILIE: Summary and future plans
Phoenix charge breeder optimization
Tests at LPSC for understanding the 1+ n+ technique
Tests with the CARIBU CB for light ions at SPIRAL
Operational upgraded Phoenix charge breeders
SPES charge breeder
See Alessio’s poster
SPIRAL charge breeder
See Laurent Maunoury’s poster
Dedicated efforts for beam purity
UHV /aluminum components and special surface treatments
Use of dedicated separators (SPES) and cyclotron (SPIRAL) mass resolving power
Simulation work at INFN
MW coupling
reproducing the 1+ beam capture DV curve
see Alessio’s presentation
ECR 1+ hot sources
being assembled at LPSC
650°C at 5.4GHz should be tested within EMILIE, 1200°C for a later stage

29. Thanks a lot for your attention!
GANIL
L. Maunoury
E. Traykov
P. Jardin
M. Dubois
P. Chauveau
LPC Caen
G. Ban
J. F. Cam
C. Vandamme
INFN LNL
Galatà
G. Patti
G. Prete
INFN LNS
L. Celona
JYFL
H. Koivisto
O. Tarvainen
ANL
R. Vondrasek
ISOLDE
F. Wenander
Shornikov
LPSC
T. Lamy
J. Angot
J. Angot, G. Ban, L. Celona, J. Choinski, , P. Delahaye (GANIL IN2P3, coord.), A. Galata (INFN, deputy coord.), 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

30. Phoenix ECRIS
Noble gases are recycled
Condensable elements are not
DV tuning necessary

31. Capture is very efficient after cooling in REXTRAP
REXTRAP - REXEBIS
Capture is very efficient after cooling in REXTRAP
Operating range
REX-ISOLDE

32. ANL ECRIS
High capture efficiency
Better 1+ beam optics
Very low residual pressure
High charge states
2 frequency heating
Very low residual pressure

33. Beam purity from REX-EBIS
Extracted beams from REXEBIS as function of A/q showing residual gas peaks and charge bred 129Cs. The blue trace is with and the red trace without 129Cs being injected.
F. Wenander, CERN courier, Jan/Feb 2012, p33

34. SPIRAL 1 & 2 post-accelerator
3 kW
1,5 kW
Ne, Ar, Kr, N, O, F He
Targets
Nanogan ECRIS source
B. Jacquot et al, GANIL status report
Suppression ~10 for R=m/dm~1/(2pHN) up to 6000
Suppression ~106 for dm/m=5.10-4
CIME cyclotron

35. ANL ECRIS charge breeder
See talk R. C. Pardo
Multiple frequency operation
Klystron: GHz, 2 kW
TWTA: 1113 GHz, 0.5 kW
Open hexapole structure
RF is injected radially
Uniform iron in the injection region for symmetrical fields
Improved pumping to the plasma chamber region
Base pressure: 2x10-8 mbar
Operation: 7x10-8 mbar
Extraction pressure: 4x10-8 mbar
What is so different?
Field symmetries
Tunable grounded tube
Excellent vaccuum
2 Frequency heating
Cold 1+ beams …?
Movable grounded tube with 2.5 cm of travel
50 kV high voltage isolation
Importance of field symmetry
R. Vondrasek et al, Rev. Sci. Instrum. 83, (2012)
Loss patterns of ions on plasma chamber and electrodes
SC Jeong et al, Rev Sci Instrum. 83, 02A910 (2012)
Design value Running condition
Binj T T
Bmin
Bext
B (radial) T
Last closed surface T

36. ECRIS optimizations
Optimizing charge states and capture efficiencies with
double frequency heating
Gas mixing
Using molecular beams (CO)
Light ions
Studies of the 1+ beam capture process
1+ beam slowing down simulations
1+ beam capture experimental investigations
Low charge states as a diagnostic for the capture
Influence on the plasma composition
Off-line tests of SPES and SPIRAL charge breeders
H. Koivisto et al, RSI 85 (2014)
L. Maunoury et al, RSI 85 02A504 (2014)
R. Vondrasek et al, Rev. Sci. Instr. 83(2012)11330
P. Delahaye et al, NIM A 693(2012)104
Phoenix ECRIS at the
LPSC test stand
T. Lamy et al., ECRIS2014, JACoW
Tests at LPSC until September 2015

37. The REX-EBIS setup The LaB6 cathode EBIS specifications
jcathode<20A/cm2
je=jtrap<200A/cm2
Ie=460mA (normal operation 200mA)
E=3.5-6keV
3 drift tubesL=200 to 800 mm
Theoretical capacity 5·1010 positive charges
Ultra-high vacuum mbar
The charge state is selected with a mass separator of Nier-Spectrometer type
Performances: F. Wenander et al.,
Rev. Sci. Instrum. 77, 03B104 (2006)
ICIS 05 Proceedings

38. Beam purity from ECRIS charge breeders
Troublesome restgas spectrum: C,N,O… + stainless steel components
Entrance of the ECR P=5.10-7mbar
Ex: Phoenix at ISOLDE
Exit P=2.10-7mbar
Background >5nA 2<A/q<7
Phoenix test