RIB production with SPIRAL 2

1
RIB production with SPIRAL 2

• Versatile and evolutive
• Fission fragments with D beam Goal gt 1013
  fissions/sfusion-evaporation with heavy ions
• Basic configuration
• ? Fission fragments produced by n-induced
  fission ? Converter d-n with a carbon wheel ?
  UCx fissile target - low or high density
  (Gatchina) ? Possibility to couple different
  ions sources (1) ? 1/n (charge breeder)
  approach

2
Fission yields
with converter ...
4.5 mA 1013 f/s ?2.3g/cm2 V240cm3 5
mA 5.1013 f/s ?11g/cm2 V240cm3 5 mA
2.1014 f/s ?11g/cm2 V1000cm3 6kW
(limit) Fission of 239U Ex 20 MeV
40 MeV deuteron, 5 mA ? 200 kW dissipation in the
converter
without converter ...
0.15mA 5.1012 f/s 6kW Fission of 240Pu,...
Ex 50 MeV
acces to a wider mass region
3
Fission yields (low density and with converter)
d (40 MeV, 4.3 mA) C UC (2.3 g/cm3, 363 g)
on target
x 10-2 - 10-3 towards experiment
4
Example production from D beam
? Sn isotopes D 4 mA on C with UCx lowdensity
target (1013 fissions/s).
UCx target
IS
Efficiencies for Sn isotopes M.G.
Saint-Laurent
T1/2 (s) Diff. Eff.-t Eff.-tube
1 1/n Acc. Total 132 40 0.31 0.83 0.99 0.3 0.0
4 0.5 1.5e-3 133 1.4 0.065 0.16 0.86 0.3 0.04 0.5
5.4e-5
5
Production from Heavy Ion Beams
Primary Heavy Ion beams at 14.5 A.MeV of 1 mA, up
to Ar
? neutron deficient RIB
Fusion-evaporation and transfer
reactions residues produced by thick target
method (like ISOL_at_GSI) example 58Ni 50Cr ?
100Sn 1 1 pps
Spectroscopy of NZ A100
? neutron rich RIB
Fusion-evaporation residues produced by thin
target method (In-Flight) example 28Ni 58Mg ?
80Zr 1 3 x 104 pps
6
Regions of the nuclear chart covered by ...
1. Fission products
2. High Ex fission products
7
Target Ion Source the Plug solution
rotating C wheel
2 m concrete ? dose rate lt 7.5 ?Sv/h
primary beam (deuterons)
Plug housing C converter and UCx target dose
rate 32 Sv/h at 1 m and 34 mSv/h after 1 year
exotic beam
8
Detail of the rotating wheel
UC2 target
Ti support
R 385 mm
Beam size 10 x 25 mm
Carbon  standard 
First study
9
DRIVER
14.5 A.MeV ions 40 MeV deuterons
Source Injector Linear accelerator

• Must be an evolutive and versatile machine
• Optimised for q/A1/3 ions and must accelerate D
  (q/A1/2)
• No stripper, to make a direct profit of the ECR
  sources evolutions for heavy ions, as far as beam
  energy is concerned
• 1 mA for ions (up to Argon) and 5 mA for
  deuterons
• Injector RFQ with a 100 Duty Cycle
• Exit Energy 0.75 A.MeV - 1.5 A.MeV (according
  to the frequency)
• LINAC Independant Phase Superconducting Cavities
• based on QWRs and/or HWRs up to 40 MeV or 14.5
  A.MeV
• Frequency 88 MHz and 176 MHz or 176 MHz for
  the whole linac
• gradient 6-8 MV/m ( Vacc / ? ? ) 30-40
  resonators

10
Main driver components
Deuteron Source ex. SILHI-type(permanent magnets)
QWR Argonne
example of ACCEL cryostat(4 cavities, 2
solenoids)
SC Solenoid steering coils active screening
RFQ (Cu plated SS version)
11
Primary Sources RD
? deuterons (5 mA) downgrade of SILHI source
or micro-phoenix or ... ? heavy ions q/A1/3 (1
mA) cw mode, voltage 60 kV, ? lt 200 ? mm
mrad state-of-the-art 18O6 1 mA 36Ar12 0.2
mA ? High Frequency high B
1. A fully superconducting ECRIS (close to the
GYROSERSE project) Bmax 4 T Brad 3 T large
ECR zone, F 28 GHz, and possibly above 2. A
compact source, with lower magnetic field
higher power density (A-PHOENIX) technology
based on HTS coils and permanent magnets Bmax 3
T Brad 1.6 T
12
Low Energy Beam Transfer (LEBT)
Goal to transport and to match and 2 types of
beam to RFQ with very low loss energy 20
keV/n D (5 mA, 40kV) q/A1/3 (1mA, 60kV)
13
Linac architecture

• Beam Dynamics studies determine the optimal
  choice of
• linac frequency
• resonator types
• transition energies (RFQ output, geometric
  betas)
• Nb of resonators / cryostat, etc ...
• and should also accelerate heavier ions (q/A1/6)
• 2 options 88/176 MHz or 176 MHz for the whole
  linac
• pros and cons
• 88 MHz requires QWRs ? easier fabrication and
  cleaning but dipole fields only partially
  compensated
• 176 MHz only ? only HWRs could be used but more
  dissipation in the RFQ, requires higher RFQ
  output energy

14
Different technological solutions for the RFQ
4-rod RFQ, IH-type RFQ ? cheaper but low-frequency
IAP Frankfurt
4-vane RFQ ? cw operation high transmission
classical brazed Cu 88 or 176 MHz
separated functions 88 MHz
with rf joints 88 or 176 MHz
Cu plated SS 88 MHz
15
Phase space at the RFQ output

Ex. 88 MHz 4-vane Length 5m Energy 0.75
A.MeV aperture 8 - 10 mm vane voltage
100 -113 kV Modulation 1-2 Transmission
99,95 (1/2) 99,93 (1/3)
1/2
1/3
16
Resonators
Legnaro-type QWR
Argonne_type QWR and HWR(with field asymmetry
compensation)
40 resonators at 6 MV/m 30 resonators at 8
MV/m
17
Beam dynamics in the SC linac

• 2 essential rules to avoid? dilution beam loss
  
• phase advance lt 90
• long. trans. matching between tanks
• ? favours large Nb cavities / tank
• solenoid instead of quad focusing
• 1 solenoid / cavity at low energy to keep
• the beam size lt the cavity aperture (30 mm max)
• Bz lt 7-8 T to keep
• classical technology
• NbTi SC solenoid

phase advance too large !
18
Schematic lay-out (1)
RFQ
CIME
Q/A 1/3ion source
DeuteronSource
Separator
charge breeder 1 / N
SC LINAC
Fission fragments lt6 MeV/nucléon
Deuteron 40 MeV Heavy ions 15 MeV/u
Low energy RIB
Target-Sourcesystem
19
Schematic lay-out (2)
post-accelerator CIME
Low energy RIB
stable heavy ions
Injection to CIME
ECR Sources(d and q/A1/3 ions)
SC LINAC 40 MeV and 14.5 A MeV
RFQ
F. Daudin
20
GANIL expansion
21
Time schedule
APD 2 years Nov 2004
22
Long-term future (1)
can be used as a post-accelerator with future
upgrade in energy
Driver light (heavy) ions
Energy upgrade
SPIRAL 2
23
Long-term future (2)
or can be used as the low energy part of a future
high energy driver
postaccelerator
production
Energy upgrade
SPIRAL 2