beam intensities with eurisol
DESCRIPTION
BEAM INTENSITIES WITH EURISOL. M. Valentina Ricciardi GSI, Darmstadt, Germany. LAYOUT. "Blocks of knowledge" to be put together to estimate RIB intensities: 1) Set-up 2) Production cross-sections 3) Production rates 4) Efficiencies 5) Possible combination of ISOL + IN-FLIGHT methods - PowerPoint PPT PresentationTRANSCRIPT
BEAM INTENSITIES WITH EURISOL
M. Valentina Ricciardi
GSI, Darmstadt, Germany
LAYOUT
"Blocks of knowledge" to be put together to estimate RIB intensities:
1) Set-up
2) Production cross-sections
3) Production rates
4) Efficiencies
5) Possible combination of ISOL + IN-FLIGHT methods
These "blocks of knowledge" are not uncorrelated.
How to proceed?
1. We go through each block and see what we know
2. Provide this information to the user in a simple, accessible way (www)
SET-UPPrimary beam
Standard option: 1 GeV protons:● on direct target (100 kW)● on converter target (4-5 MW)
Additional possibilities (compatible with the baseline driver accelerator):● 2 GeV 3He● 250 MeV deuterons● heavier ions with A/Q = 2 up to 125 MeV/u
Target
Direct target Protons interact directly with the target material
Indirect target Spallation neutron source (most of the heat load) Production target (few-MeV neutrons)
Which nuclear reactions are of interest assuming the above set-up?
Direct-target option
Spallation-evaporation with ≤ 1 GeV protonsSpallation-fission with ≤ 1 GeV protonsFission with secondary neutrons
Indirect-target option
Fission with few-MeV neutrons
PRODUCTION CROSS SECTIONS
Experimental data taken at the FRS at GSI
Features of spallation reactions
Spallation-evaporation produces nuclides reaching from the projectile to about 10 to 15 elements below (a few of them are neutron-rich, most of them are neutron-deficient)
Spallation-fission (from Th, U) produces neutron-rich nuclides up to Z=65.
IMF (intermediate-mass fragments)
Fission fragments
Evaporation residues
PRODUCTION CROSS SECTIONS
P. Napolitani J. Taieb, M. Bernas, V. Ricciardi
The region on the chart of the nuclides covered by evaporation residues extends with increasing
energy available in the system
Experimental data taken at the FRS at GSI Energy dependence
Useful to:
• Fill gaps in target mass
• Enhance the production of IMF
PRODUCTION CROSS SECTIONS
B. Fernandez
T. Enqvist
T. Enqvist
Fission. Model Calculation (ABLA)
PRODUCTION CROSS SECTIONS
K. H. Schmidt, A. Kelić
PRODUCTION CROSS SECTIONSSpallation. Model Calculation (ABRABLA)
IN-TARGET PRODUCTION (production rates)
Additional things enter into the game:
a. Target thickness, materialb. secondary projectiles (mostly neutrons)c. decay pattern
Important: target material should be feasible!
U. Köster
IN-TARGET PRODUCTION (production rates)
Residue production in thick-spallation targets (D. Ridikas)
J.-C. David et al, Internal report DAPNIA-07-59, June 2007
Fission residue: Evaporation residue:
Experiment: at Dubna, Pohorecki et al, NIMA 2006
Calculations: MCNPX2.5.0 + CINDER'90
660 MeV p30.8 cm natPb
Optimization of in-target yields: Direct targets
Optimum target: Pb Optimum energy: 1 GeVOptimum target length: ~18 cm? (extraction efficiency)
Case 183Hg
Courtesy of S. Chabod
IN-TARGET PRODUCTION (production rates)
EFFICIENCIES
Specific and precise information on the efficiency, nucleus by nucleus(CERN/ISOLDE)
On progress
In the meantime, profiting of the valuable database(*) of yields at ISOLDE, a work of Lukić gives anOverview on the overall extraction efficiency(GSI)
(*) H.-J. Kluge, Isolde users guide, CERN, Geneva, 1986, web: http://isolde.cern.ch
EFFICIENCIES
Correlation of ISOL yields with isotope half-life
Comparison of ISOLDE-SC yields to in-target production rates
Ratio yield/produced → overall extraction efficiency for the nuclide
S. Lukić et al.
EFFICIENCIES
Same general behavior found in many cases.
0
21
s
21
t
t1
t
S. Lukić et al.
EFFICIENCIESK.H. Schmidt
EFFICIENCIES
Can we extract some
general tendency from the measured
data?
...work in progress
K.H. Schmidt
J. Benlliure et al
GSI experiment S294 (November 2006)
Participating institutes:Universidad de Santiago de Compostela, SpainCentre d’Etudes Nucleaires Bordeaux-Gradignan, FranceWarsow University, PolandGSI Darmstadt, GermanyVINCA-Institute Belgrade, SerbiaInstitute of Physics, Bratislava, Slovakia
TWO-STEP REACTION: ISOL + IN-FLIGHT
What is cold fragmentation
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
TWO-STEP REACTION: ISOL + IN-FLIGHT
Experimental setup at FRS
GSI experiment S294 (November 2006)
S0-S2: 238U(950 A MeV) + Be 132Sn
S2-S4: 124-132Sn + Be X
A/A ~ 1 10-3
B/~ 3 10-4 ToF ~ 100 psL ~ 36 m
B/~ 3 10-4 ToF ~ 72 psL ~ 18 m A/A ~ 1.3 10-3
Z
BAcm
e
0
Z2 ~ E
TWO-STEP REACTION: ISOL + IN-FLIGHT
Fragmentation of 132Sn (Preliminary results)
Fragmentation of 132Sn on BeD. Perez and D. Dragosavac
TWO-STEP REACTION: ISOL + IN-FLIGHT
Preliminary cross sections are available
Energy of the post accelerator
Charge state can cause impurity
TWO-STEP REACTION: ISOL + IN-FLIGHT
BEAM-INTANSITY DATA-BASE
Courtesy of Wojtek Gawlikowicz, Univ. Warsaw
http://www-w2k.gsi.de/eurisol-t11http://www.slcj.uw.edu.pl/~wojtek/eurisol_database.php
• Consistent description of nuclide production
• Calculations of in-target yields in progress
• Study of the extraction efficiencies in progress
• Feasibility of the two-step reaction scheme experimentally proven
• EURISOL beam-intensities data-base in progress
CONCLUSIONS
Beam intensities with EURISOLEURISOL DS Task 11
Task leader: Karl-Heinz Schmidt, GSI-Darmstadt
Participants and contributors: ISOLDE-CERN, CEA/Saclay, University of Jyväskylä, University of Warsaw, IoP Bratislava, GSI-Darmstadt, University Santiago de Compostella, Khlopin Radium Institute, VINČA-INS Belgrade