Beam intensities with EURISOL

1
Beam intensities with EURISOL Aleksandra Kelic,
GSI-Darmstadt on behalf of the EURISOL DS Task
11 Participants and contributors ISOLDE-CERN,
CEA/Saclay, University of Jyväskylä, University
of Warsaw, IoP Bratislava, GSI-Darmstadt,
University Santiago de Compostella, Khlopin
Radium Institute, VINCA-INS Belgrade
2

Steps towards final beam intensities
Production cross sections experimental and
calculated
Production cross sections experimental and
calculated
Transport phenomena
Transport phenomena
Extraction, ionisation and acceleration
Constraints usable primary-beam intensity and
the usable target thickness Technical
limitations of the primary accelerator ? max
possible Ibeam Heat load in the target ? max
usable Ibeam The energy loss of the beam ? max
usable Ltarget The attenuation of the beam along
its path ? max usable Ltarget
3
See also P26 S. Chabod et al, "Optimization of
the target in terms of secondary beam
intensities" P29 P. Delehaye et al, "Towards
high intensity energy ISOLDE Extrapolation of
yields for accelerated isotopes at
REX-ISOLDE" P50 D. Perez et al, "Fragmentation
of very neutron-rich projectiles around
132Sn" P52 J. Ronkainen et al, "Independent
elemental fission yield distributions with
JYFLTRAP" P55 M. Veselsky et al, "Production of
neutron-rich nuclei in nucleus-nucleus collisions
at energies around below Fermi energy"
4

Two-step reaction mechanism J. Benlliure et
al GSI experiment S294 (November 2006)
Participating institutes Universidad de Santiago
de Compostela, Spain Centre dEtudes Nucleaires
Bordeaux-Gradignan, France Warsow University,
Poland GSI Darmstadt, Germany VINCA-Institute
Belgrade, Serbia Institute of Physics,
Bratislava, Slovakia
5

Two-step schemes fission cold fragmentation
Production of medium-mass neutron-rich nuclei
1. Produce 132Sn via fission in uranium target
2. Use cold fragmentation of 132Sn to produce
medium-A neutron-rich nuclei
6

Experimental setup at FRS GSI experiment S294
(November 2006)
S0-S2 238U(950 A MeV) Be ? 132Sn
Z2 DE
S2-S4 124-132Sn Be ? X
7
Fragmentation of 132Sn (Preliminary results)

Fragmentation of 132Sn on Be
D. Perez and D. Dragosavac (see P50)
8
Production cross sections
Courtesy of David Perez, USC (see also P50)
Model calculations COFRA and EPAX
9
Improvements in the GSI evaporation/fission code
ABLA A. Kelic, M.V. Ricciardi and K.-H.
Schmidt, GSI-Darmstadt
10
Benchmark calculations on residue production
Thick targets (EURISOL Internal report), J.-C.
David et al, CEA Saclay
p(1.4 GeV) UCx ? Ne
Problems in the previous version of the ABLA code
for nuclei far below the target mass.
11
ABLA07
Evaporation stage - Emission of IMFs (sequential
and simultaneous) - Particle decay widths -
energy-dependent inverse cross sections based on
nuclear potential - thermal expansion of
emitting source - angular momentum in particle
emission - g-emission at energies close to the
particle threshold (A.V. Ignatyuk, 2002) Fission
stage - Influence of nuclear viscosity on the
fission decay width - analytical
time-dependent approach (B. Jurado et al, 2003)
- influence of initial conditions - Particle
emission on different stages of the fission
process
12
Exp - R.Michel et al., NIM B129 (1997)
153 Calculations BURSTABLA, BURSTABLA07
13
Comparison with data measured at GSI
Data available at http//www.gsi.de/charms/data.h
tm
14

• In-target yields calculations
• V. Blideanu, S. Chabod, J.-C. David, D. Doré, D.
  Ene, D. Ridikas, N. Thiollière et al
• CEA Saclay

15
Residue production in thick-spallation targets
J.-C. David et al, Internal report DAPNIA-07-59,
June 2007
Experiment at Dubna, Pohorecki et al, NIMA
2006 Calculations MCNPX2.5.0 CINDER'90
16
Optimization of in-target yields Direct targets
Courtesy of S. Chabod (see also P26)
Case 183Hg
Optimum target length 18 cm? (extraction
efficiency)
Optimum target Pb
Optimum energy 1 GeV
17
Final goal Beam intensities data-base
Courtesy of Wojtek Gawlikowicz, Univ. Warsaw
18
Conclusions

• Feasibility of the two-step reaction scheme
  experimentally proven
• Consistent description of nuclide production
• Calculations of in-target yields in progress
• First steps towards EURISOL beam intensities
  data-base

19
? exp - R.Michel et al., NIM B103 C.M.Herbach
et al., Proc. of the SARE-5 meeting, 2000
20
In-target yields Example Calculated production
rates of Sn isotopes for the realistic
single-stage target (UCx) configuration
D. Ridikas et al, CEA Saclay