Techniques avances de manipulation dions radioactifs

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Techniques avancées de manipulation dions
radioactifs
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Dans quel contexte?
The chart of the nuclidesAn open landscape for
investigations

• In
• Nuclear physics
• Structure, magic numbers, deformations, haloes,
  Superheavy elements, nuclear equation of states,
  reaction mechanisms
• Nuclear Astrophysics
• Nucleosynthesis, r and rp processes, supernovae
  explosions, X ray bursts
• Weak Interaction physics and fundamental
  symmetries
• CVC, CKM Unitarity, Exotic interactions
• Solid State physics
• Medical Applications!

From the EURISOL report http//www.ganil.fr/euriso
l/Final_Report.html
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Quel type de manipulation?

• Caractéristiques dun faisceau dions
• M(A,Z)
• q
• Energie
• Emittances

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Des exemples
DISOLDE
Et dailleurs

• ISOLTRAP
• WITCH
• REX-ISOLDE
• ISCOOL

• LPCtrap, LPC et GANIL
• MOT _at_ TRIUMPH
• MOT _at_ ANL
• ATHENA _at_ CERN

• MATS
• EURISOL
• RIA _at_ MSU
• Beta-beams

Les projets
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Zoologie (1)

• Les charge breeders élévateurs de charge

ECR charge breeder
EBIS
Des sources dions pour la transformation 1?n
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Zoologie (2)

• Les pièges électromagnétiques

• Penning traps

• Paul traps

ion traps

• Magnetic Optical Traps (MOT)

atom trap
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ISOLDE

• EBIS
• ECRIS
• Penning Trap
• Paul Trap

Elévateur de charges et pièges électromagnétiques
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A charge breeder

• ECR booster vs EBIS stripping foils

REX-EBIS Operational at REX-ISOLDE
Phoenix ECRIS 14GHz Test stand at ISOLDE

• Singly charged ions ?n ions transformation
• More post-accelerated beams available
• More radioactive isotopes available
• Better purity in some cases
• Some applications for physics experiments of
  charge bred beams
• Efficiency 1 - 20 in one charge state
  depending on Z

Molecular sidebands from the ISOLDE targets
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The 1?n scenarioat ISOL facilities

• ECR breeder vs EBIS stripping foils
• Stripping foils requires a pre-accelerator
• Usually limited to small A/q

Accelerator
ISOL target
1 ion source
1? n
1 separator
A/q separator
Studied in the frame of the EURISOL and RIA
projects
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Elevation de charge dans une source ECR
R. Geller, Electron Cyclotron Resonance Ion
Source and ECR plasmas, IOP, Bristol, UK, 1996.
nef2RF
fRFqBECR/m
Régime naturellement continu, peut être pulsé
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Elevation de charge dans une source EBIS
E. D. Donets, V. I. Ilyushchenko and V. A.
Alpert, JINR-P7-4124, 1968 E. D. Donets, Rev.
Sci. Instrum. 69(1998)614
Etat de charge moyen
qlog(j.t)
Capacité de charges élementaires
Q3.36 1011L.Ie/E-1/2
Contrôle de létat de charge
Régime essentiellement pulsé
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Comparaison en cours
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Pièges de Paul
H. Dehmelt
W. Paul
Nobel Prize 1989
Potentiel quadrupolaire
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Ion motion in Paul traps
Stability diagram
Micromotion wm(1-b/2)W Secular motion wMbW/2
with bz
Matthieu parameters
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A RFQ cooler
Expected ISCOOL transmission 100 (less than
100nA) Radius a few mm Bunch time width a few µs
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Experimental technique
courtesy of K. Flanagan COLLAPS collaboration
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Cold and bunched beams for Collaps
R
Current limiting factors for laser spectroscopy

• Background of scattered laser light detected by
  PMT 2000/s.
• Detection efficiency within the light
  collection region.
• Broadening of lineshape due to voltage ripples.

Within the light collection region the ion beam
should have zero divergence (parallel beam)
Currently the minimum ion beam diameter reached
is 6mm
In order to maximize the detection efficiency
good overlap between laser and ion beams is
necessary
This results in a high background level from
scattered light
K. Flanagan COLLAPS collaboration
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Cold and bunched beams for Collaps

• A reduction in the ion beam diameter will allow
  the laser to be reduced in diameter (and
  therefore power) with no detrimental effect on
  the detection efficiency.
• Immediate consequences for the detected
  background

Bunching ions in the RFQ cooler
Trap and accumulates ions typically for 300 ms
Releases ions in a 15 µs bunch
Background suppression equal to the ratio of the
trapping time to the bunch width 300ms/15 µs
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K. Flanagan COLLAPS collaboration
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JYFL experiment
K. Flanagan COLLAPS collaboration
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ISCOOL off-line tests
HT rack
ISCOOL
Alkali ion source LPC Caen
Emittance meter CSNSM
Extraction electrodes ISOLTRAP
Inj triplets
He inlet
FC 1
FC 2
Emittance-meter
Ion source

• Bias
• Extraction
• Lens1
• Lens2
• Steering x,y

Turbopumps
3/10
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Résultats préliminaires
Sans gaz buffer Sortie RFQ
Avec gaz buffer Sortie RFQ
05/12/06
PRELIMINARY
3.6p.mm.mrad 4 transmission
2.2p.mm.mrad 70 transmission
85pA of 133Cs at 30KeV, with He flow of 8X10-1
mbar l/s
5pA of 133Cs at 30KeV, without any cooling
Sources ISOLDE 20.p.mm.mrad
RFQ cooler (avec gaz) 2p.mm.mrad
70 transmission
Pas de mesure de lémittance de la source
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Résultats préliminaires (2)
PRELIMINARY
Dispersion en énergie 1.5 eV avant
postaccelération
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Ion circus
D. Lunney and E. Minaya-Ramirez
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A Paul trap as the center of the detection setup
LPCTRAP collaboration, at GANIL
- Transparent Paul trap, UHV - Ions confined in
the middle of the device, nearly at rest - In
coincidence detection of the electron and the
recoil ion
b particle
Recoil ion
Beta telescope Silicone stripped detector
Scintillator
MCP Delay lines anode

• In coincidence measurement of
• the time of flight of the recoil ion tR
• the beta particle energy Eb
• the angle between these two particles qer

Pierre Delahaye et al., Hyp. Int. 132(2001)479
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The b-n angular correlation in nuclear b decay
b decay spectrum
a

• Fermi transition (DJ0)

• Gamow-Teller transition (DJ01)

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The b-n angular correlation in nuclear b decay

• Test of the V-A theory
• Sensitive to exotic interactions S,T

• Pure Fermi transitions

• Pure Gamow Teller transitions

V-A aGT-1/3
V-A aF1
Johnson et al. (1963!)
Adelberger et al. (1999)
32Ar
6He
if
if


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Experimental setup
RFQ cooler buncher
pulse down
Paul trap chamber
SPIRAL beam
HT
LPCTRAP collaboration
DSSD scintillator
20 cm
Monitor MCP
MCP DL anode
"Ring" trap
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First TOF spectrum
LPCTRAP collaboration, at GANIL

• conditioned spectrum

(V-A theory)
Oscar Naviliat, Scientific council of GANIL, June
2005
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Ion motion in the Penning traps
Superposition of a magnetic and electric
quadrupolar field
Frans Michel Penning
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Refroidissement et regroupement
DE
Accumulation
Refroidissement
Éjection
Sideband Cooling
force de friction F -? m v ? r (t) ? r(0) e
-?/2 t exemple Na 10-4 mbar Ne d 400
s-1 trefroidissement20 ms
Excitation quadrupolaire à la fréquence wcqB/M
dans le plan transverse du piège Couplage des
mouvements magnétron et cyclotron
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REXTRAP à REX-ISOLDE
Refroidissement et regroupement
Superconducting magnet 3T PNe 10-4 mbar in the
trapping area
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Performances
P. Schmidt et al, Nucl. Phys. A 701(2002)550
breeding time (A/q lt 4.5) 20 msbeam
intensities lt 109 /sions in one charge state
lt 30injection efficiency into EBIS
gt80efficiency REXTRAP 50
Un piège très large de grande capacité Limitations
de charge despace 108 ions/ cycle
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Méthode de refroidissement sélective en masse

• Excitation magnétron dipolaire
• Décentre les ions

• Excitation magnétron dipolaire
• Recentre les ions wrfwcqB/m

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Charge despace
Observed resonance frequency shift and broadening
as function of the number of ions
D. Beck et al, Hyp. Int. 132(2001)469
Diploma thesis Sven Sturm
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Résultats de simulation
Measured resonance with 5 106 133Cs ions in
Rextrap
Simulated resonance with 1 107 133Cs ions,
normalised to Rextrap magnetic field
Diploma thesis Sven Sturm
Work in progress
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Tests de séparation en ligne
Resolving 2pA N2 (lower frequency) and 1.5pA CO,
both mass 28 (Error bars derived from statistical
fluctuations)
Resolving approx. 0.8pA 40K (lower frequency) and
0.8pA 40Ca (Errror bars derived from statistical
fluctuations) Resolving Power4.5 104
Diploma thesis Sven Sturm
Work in progress
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The ISOLTRAP mass spectrometer
Precision measurement of wcqB/m
Stable alkali reference ion source
Precision trap
ISOLDE beam 60 keV
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Ion motion manipulation
TOF vs. excitation frequency
Scan QP-excitation freq. nrf about nc
Magnetron excitation
Quadrupolar excitation nrf
Radial energy ? axial energy
Magnetron excitation r?
Cyclotron excitation r
TOF resonance
Relative accuracy (dm/m) 10-7
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Excitation Ramsey
TOF / µs
T1
T1
T0
Frequency detuning / Hz
S. George et al., Int. J. Mass Spectrom., in
preparation (2006).
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The Mass of 38Ca
T1/2 440 ms
A statistical uncertainty of about 2?10-9 is
obtained in less than one hour.
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The physics aims

• The mass as a fundamental quantity for
• Reactions (Q values)
• Nuclear models
• Nuclear Structure (S2n) shell closure, magic
  numbers, deformations, IMME
• Astrophysics - waiting points, decay rates
• Weak interaction physics - Tests of CVC and the
  unitarity of the CKM matrix

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Refinement of the mass surface

• S2nB(N,Z)-B(N-2,Z)

N 50 shell closure
Deformation
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Mid-shell effects around N40
N40
Cu,Ga, Ni isotopic chains measured Céline
Guénault et al, in preparation
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FT value measurements
Superallowed b transitions 0 -gt 0

• Comparative half-life

• corrected ft

Is constant in the CVC hypothesis
dR radiative correction dC isospin
symmetry-breaking correction DRV nucleus
independent radiative correction
fQ5
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CVC test
ISOLTRAP mass measurements 22Mg ? 22Na dQ0.28
keV, 34Ar ? 34Cl dQ0.41 keV, 74Rb ? 74Kr
dQ4.5 keV
CVC hypothesis confirmed in this mass region
I.S. Towner J.C. Hardy, Phys. Rev. C 71,
055501 (2005)
LEBIT 38Ca
74Rb
66As
Limit from QEC(38Ca)
JYFLTRAP
CPT 46V
22Mg
JYFLtrap new!
62Ga
34Ar
From Klaus Blaum, NUPAC meeting at ISOLDE
2005/10/11
F. Herfurth et al., Eur. Phys. J. A 15, 17
(2002) A. Kellerbauer et al., Phys. Rev. Lett.93,
072502 (2004) M. Mukherjee et al., Phys. Rev.
Lett. 93, 150801 (2004)
T. Eronen et al., to be published (2005) G.
Savard et al., Phys. Rev. Lett. 95, 102501 (2005)
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MATS
Super FRS
Gas Catcher
EBIT charge breeder
Penning trap
m/q selection
10-100 times higher yields than everywhere else
1 50 times higher resolving power as compared
to 1
factor of 10 - 5000 shorter half-lives higher
resoving power and precision beam time saving
??m/m lt 1?10-8 on isotopes with T½ ? 100 ms ?
perfect match with FRS LEB capabilities
By courtesy of Klaus Blaum, Mainz
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Setup

• Detectors
• FT-ICR
• TOF-ICR
• Si(Li) electron

Precision trap mass measure- ments
Cooler trap beam preparation spectroscopy
Magn. deflector q/m separation
EBIT charge breeding
By courtesy of Klaus Blaum, Mainz
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Experiments with exotic nuclei

• Detectors
• FT-ICR
• TOF-ICR
• Si(Li) electron

T1/2 ...
Mass
Precision trap mass measure- ments
Laser Spectroscopy
Cooler trap beam preparation spectroscopy
Magn. deflector q/m separation
EBIT charge breeding
X- ray Spectroscopy
In-Trap Spectroscopy
By courtesy of Klaus Blaum, Mainz
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Avantage des ions multichargés
- much higher resoving power and precision -
reduced beam time requirement
By courtesy of Klaus Blaum, Mainz
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The WITCH retardation spectrometer
The WITCH experiment IKS Leuven at ISOLDE
35Ar decay Search for scalar interaction
Recoil ion energy spectrum
D. Beck NIM A 503(2003)567
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ATHENAProduction dantihydrogène
Antiproton capture trap Deceleration and capture
of antiprotons Penning trap in 3-T field at 15
K Cooling and accumulation in e- plasma
22Na source Positron production via 22Na(ß)22Ne
at 5.5 K Positron accumulator Penning trap in
0.14-T field at 300 K
Mixing trap Antihydrogen production Nested
Penning trap in 3-T field at 15 K Detector
M. Amoretti et al.,NIM A 518 (2004) 679
By courtesy of M. Doser
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Mixing trap

• Refroidissement des antiprotons interagissant
  avec les positrons
• Refroidissement des positrons par rayonnement
  synchrotrons

But spectroscopie laser de haute précision de
lantihydrogène pour tester CPT
By courtesy of M. Doser
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Atom motion in MOT
S. Chu, C. Cohen Tannoudji and W. D.
Phillips Nobel Prize 1997
Tlt200µK
So cold that (Tlt100nK)
Bose Einstein condensate
E. Cornell, W. Ketterle, K. E. Wieman
Nobel Prize 2001
X. Fléchard et al., LPC Caen
Velocity-distribution data confirming the
discovery of a new phase of matter, the
BoseEinstein condensate, out of a gas of
rubidium atoms.
From Wikipedia
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The TRINAT experiment at TRIUMF
A MOT as the center of the detection setup
J. Behr et al, Phys. Rev. Lett. 79, 375
A. Gorelov et al, Phys. Rev. Lett. 94, 142501
e- shakeoff
From Dan Melconian, PhD, Triumf
55
6He - Single Atom Spectroscopy
Courtesy of Peter Müller, Argonne Nat. Lab
56
6He - Nuclear Charge Radius
Isotope shift(23S1 - 33P2, 6He 4He) 43
194.772(56) MHz 6He rms charge radius 2.054(14)
fm (0.7)
Modelindependent!
Atomic isotope shift
This work
Experiment
Reaction collision
Tanihata 92
Elastic collision
Alkhazov 97
Csoto 93
Funada 94
Cluster models
Varga 94
Wurzer 97
Theory
Esbensen 97
No-core shell model
Navratil 01
Pieper 05priv. comm.
Quantum MC
L.-B. Wang et al.,PRL 93, 142501 (2004)
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Quelle place dans EURISOL?
Advanced techniques for the Radioactive ion beam
manipulation
More radioactive beams for more available
energies! Beta-beam aspect
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Beta-beam

• CERN baseline scenario

- like
Etude des oscillations ne lt-gt nm Utilisation du
boost de Lorentz de faisceaux emetteurs b
accélérés pour la création de faisceaux de
neutrinos purement électroniques 6He et 18Ne
1012- 1013/s en bunch de 50ms, 10 Hz
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60 GHz ECR Ion Source Prototype

• Will enable pulse study in
• Afterglow mode
• 1 n ECRIT mode
• Preglow mode

T. Lamy and T. Thuillier
High Magnetic Confinement for optimal 60 GHz
Microwave injection
Collaboration avec lIAP de Nizhniy Novgorod
Klystron à 37.5 GHz and 75 GHz
Etude des modes pulsés de la source ECR
afterglow et preglow
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Manipulation du faisceau pour RIA

• Des faisceaux basse énergie pour les
  installations in-flight

ISOLDE, GANIL/SPIRAL, TRIUMF,
GSI (FAIR project), MSU, ANLRIA
61
Gas stopping of fast projectile fragments

• Study of gas stopping of fast beams ( gt50 MeV/u )
  in linear gas cells
• NSCL (high-pressure gas cell ) 90 - 150 MeV/u
  Si, P, Ca, S, Ge, As, Se, Br NIM
  A540(2005)245, NIM A522(2004)212, NIM
  A531(2004)416, Nucl. Phys. A746(2004)655c
• RIKEN (low-pressure gas cell) 50 -70 MeV/u
  Li, Be Rev. Sci. Instr. 76(2005)103503, NIM
  A532(2004)40, NIM B204(2003)570
• GSI (low-pressure ANL gas catcher) 280 MeV/u Cr
• Linear gas cells work NSCL first to start
  experimental program with stopped fast beams
  (LEBIT) Penning trap mass measurements of rare
  isotopes from projectile fragmentationSince
  summer 2005 33Si, 29P, 34P, 37Ca, 38Ca, 40S,
  41S, 42S, 43S, 44S, 63Ga, 64Ga, 64Ge, 65Ge, 66Ge,
  66As, 67As, 68As, 80As, 68Se, 69Se, 70Se, 81Se,
  81mSe, 70mBr, 71Br

• Linear gas cells have limitations!
• Rate-dependent extraction efficiencies limit
  experimental opportunities
• Average extraction times of about 100 ms do not
  match advantages of in-flight production

Ionization rate density is critical parameter ?
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An advanced concept - the cyclotron gas stopper
Gas-filled focusing cyclotron magnet RF
guiding techniques
Separation of stopped-ion distribution and region
of maximum ionization
? Beam rate capability gt 108/s for 100 MeV/u
fragments
Low pressure (10 mbar typical) short extraction
path
? Extraction times lt 10 ms
G. Bollen et al., NIM A550 (2005) 27

• Concept fulfills requirements of next generation
  facility
• Full scale system under design at MSU will be
  used at ISF

63
Conclusions

• Les techniques de manipulations de faisceaux
  radioactifs
• Variétés de techniques, émergence des pièges
  électromagnétiques
• Préparation des faisceaux à basse énergie avant
  post-accélération
• Expériences de précision à basse énergie
• Des éléments incontournables pour les projects
  futurs
• Moyen terme GSI, DESIR_at_SPIRAL II, HIE-ISOLDE,
• EURISOL, RIA, Beta-beams

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Merci de votre attention!
REX-ISOLDE
R. Savreux, T. Sieber, F. Wenander, D. Voulot, P.
Delahaye and the REX-ISOLDE collaboration
The IS397 collaboration
C. J. Barton, K. Connell,T. Fritioff, O. Kester,
T. Lamy, M. Lindroos, M. Marie-Jeanne, P.
Sortais, P. Suominen, G. Tranströmer, F.
Wenander, P. Delahaye,
ISOLTRAP
G.Audi, K. Blaum, G. Bollen, D.Beck, C. Guénaut,
F. Herfurth, A. Herlert, A. Kellerbauer, H.-J.
Kluge, D. Lunney, S. Schwarz, L. Schweikhard, C.
Weber, C. Yazidijan , P. Delahaye ..., the
ISOLTRAP and ISOLDE collaboration
LPC CAEN (LPCtrap collaboration)
Gilles Ban, Guillaume Darius, Dominique Durand,
Xavier Flechard, Mustapha Herbane, Marc Labalme,
Etienne Lienard, François Mauger, Alain Mery,
Oscar Naviliat, Pierre Delahaye
65
A mass separator

• A mass separator

ISOLDE HRS upgrade Tim Giles CERN
AB-OP Rm/dm4000 in best cases Upgrade R10,000
Better Beam purity High acceptance 100
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REXEBIS
The EBIS superconducting magnet
The LaB6 cathode

• EBIS specifications
• Super conducting solenoid, 2 T
• Trap length lt0.8 m
• Electron beam, lt0.3 A and 3-6 keV
• Breeding time 3 to gt200 ms
• lt50 ms extracted bunches
• Ramped HT potential 20-60 kV
• Warm bore
• capacity up to 6.1010 charges

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The EBIS setup
The charge state is selected with a mass
separator of Nier-Spectrometer type
98 ms breeding Radioactive 110Sn 9 breeding
efficiency in 27
68
Experiments by REX-ISOLDE

• Mainly nuclear spectroscopy experiments
• B(E2) measurements with MINIBALL transfer
  reactions and Coulomb excitations

Miniball cluster
CD detector
69
Coulomb excitation of 70Se
Measurement of the B(E2) of 70Se for validation
of the shape coexistence in the mass 70
region IS397 collaboration D. Jenkins, P.A. Butler

• Mass 70 contamination of 70Ge from the usual
  ZrO target
• Solution molecular sidebands from the target
  70SeCO

REXEBIS gt5 SeCO?Se19
gt50 efficiency for SeCO cooling
REXTRAP
First run partly successful this year, should be
renewed next year
70
Different cooling schemes
Time of flight out of REXTRAP
Molecular break-up
V
120 eV
80 eV
X
V
SeCO molecule trapping
30 eV
15 eV
X
71
The HITRAP Project for Highly Charged IonsGSI
Darmstadt
Courtesy of W. Quint and the HITRAP collaboration
UNILAC
cooler Penning trap
experiments with particles at rest or at low
energies
post- decelerator
400 MeV/u
SIS

• EXPERIMENTS WITH HIGHLY CHARGED IONS AT EXTREMELY
  LOW ENERGIES
• stable and radioactive isotopes
• collisions at very low velocities, surface
  studies
• laser and x-ray spectroscopy
• g-factor measurements of the bound electron
• fundamental constants
• mass measurements of extreme accuracy
• polarization of radionuclides, decay
  spectroscopy of
• highly charged radionuclides

U73
U92
U92
ESR
electron coolingand deceleration down to 4 MeV/u
72
HITRAP at the Experimental Storage Ring ESR
Courtesy of W. Quint and the HITRAP collaboration
Precisiontrap

• Operational Parameters
• Deceleration from 4 MeV/u to keV/u
• HCI with M/q ? 3
• Beam intensity some
• 105 ions/pulse for U92
• Repetition time 10 s

MAX-EBIS
Other experimental setups(beam line height 1.25
m)
5 keVq
Re-injection channel
LEBT
verticalbeam line
73
GSI Future Project FAIRFLAIR - Facility for
Low-Energy Antiproton and Ion Research

• NESR
• Pbar ions
• 30 400 MeV
• LSR
• Standard ring
• Min. 300 keV (CRYRING)
• USR
• Electrostatic
• Min 20 keV (MPI KP HD)
• HITRAP
• Pbars and ions
• Stopped extracted _at_ 5 keV
• (under construction for ESR)

energy range 400 MeV 1 meV