The energy deposition profile for 238U ions with energies 500 and 950 MeV/u in iron and copper.

1
The energy deposition profile for 238U ions with
energies 500 and 950 MeV/u in iron and
copper. A.A.Golubev1, A.V.Kantsyrev1,
V.E.Luckjashin1, A.D.Fertman1, 1 Institute of
Theoretical and Experimental Physics (ITEP),
Moscow, Russia A.V.Kunin2, V.V.Vatulin2,
Yu.V.Panova2, 2Russian Federal Nuclear Center -
All-Russia Research Institute of Experimental
Physics (RFNC-VNIIEF), Sarov, Russia E.Mustafin3,
D.Schardt3, K.Weyrich3, I.Hofmann3, 3
Gesellschaft fur Schwerionenforschung (GSI),
Darmstadt, Germany N.M.Sobolevsky4,
L.N.Latysheva4. 4 Institute for Nuclear Research
of Russian Academy of Sciences (INR RAS), Moscow,
Russia.
2
Introduction We present the results of precision
measurement of the energy deposition profile of
the U ions of energy E500 and 950 MeV/u in
copper and stainless steel targets performed in
GSI. Comparison of the measured data with the
dE/dx calculations using the ATIMA, SRIM and
SHIELD codes is discussed. These data are
important for the design of the SIS-100 and
SIS-300 synchrotrons of the GSI FAIR Project, as
well as in various fields of fundamental and
applied science, in particular for studies of
high density energy contribution in a matter
produced by heavy ion beams.
3
The thick target method and its advantages 1)
it provides a direct measurement of the energy
deposition function, rather than its
reconstruction from the differential energy
deposition measurements using thin foils 2) it
eliminates the edge effects as compared to the
thin foil approach 3) it takes into account
the beam straggling and fragmentation, secondary
particles etc.
4
The target consists of two wedges, with precise
control of the angle (50) and surfaces of optical
quality. The gap between the two wedges is about
100?m. Manipulator consist of the linear motor
actuator, the control unit and a PC with
software. The axial resolution of the manipulator
is about 50?m. This allows to set the total
thickness of the wedges with a precision of about
2 ?m.
5
The oscilloscope is used to record the signal
from the calorimeter. The time of growth of the
signal amplitude (3 s) is defined by the rate of
dissipation of absorbed thermal energy in the
volume of the foil. Then the temperature of the
foil starts to decrease exponentially. The time
constant of the calorimeter (of signal decreasing
e times) is 10 s. The sensitivity is 5mV/J.
The calorimeter measures the change of
temperature in a thin layer of material
(Receiving platform) due to heating by the ion
beam. Two thermo-elements transform the
temperature increment to the electrical signal.
The foil thickness is less than 1 of the total
stopping range. The calorimeter is enclosed in a
metal case, thermo-modules are fixed in a massive
thermostat. The size of the device is Ø50x11mm,
the aperture is Ø15 mm, The error of deposited
energy measurement is 7.
6
Copper
Stainless steel
500 MeV/u
950 MeV/u
7
(No Transcript)
8
SHIELD 1
Cu cylinder
Ion Beam
SHIELD 2
Al 100 ?m
Al 150 ?m
Ti 30 ?m
Al 100 ?m
Al 250 ?m
Cu Target
Ion Beam
Monitor
Calorimeter foil
Variable thickness
9
Contribution to energy deposition from various
generations of secondary particles and fragments
in Copper target. Calculation with the SHIELD
code.
10

• Conclusion
• Precision measurements of the energy deposition
  by 238U ions of E500 MeV/u and 950 MeV/u in
  Copper and Stainless steel were performed at the
  GSI SIS18 facility.
• Detailed comparison of the measurement with
  calculations using the ATIMA, SRIM and SHIELD
  codes for the case of 950 MeV/u U-ions in Copper
  was performed.
• On the plateau the energy deposition calculated
  with the SHIELD code underestimates the measured
  values of about 20-30 while the ATIMA code
  agrees with the measurement well.
• The height of the Bragg curve in the peak from
  ATIMA and SHIELD coincides with the measurement
  within experimental accuracy.
• The stop range calculated by ATIMA agrees with
  the measured range within 3. The discrepancy of
  the range calculated with SHIELD is about 10 and
  with SRIM is about 15.
• Calculation of the stopping power for heavy ions
  in the SHIELD code according to Bethe-Bloch
  equation should be updated.

11
Recent version of the SHIELD code
1. Transport of N, ?, K, N and arbitrary nuclei
(A,Z) up to 1 TeV/u. 2. Extended target as a
combination of bodies limited by second
order.surfaces (CG-compatible) 3. Arbitrary
chemical and isotope composition of materials in
the target zones.
4. Ionization loss, fluctuation of ionization
loss and multiple Coulomb scattering of
charged hadrons and nuclear fragments. 5. 2- and
3-particle modes of meson decay. 6. Modeling of
hA- ? AA-interactions in exclusive approach
(MSDM-generator). 5
7. Memorizing of each hadron cascade tree during
its simulation without loss of physical
information. 8. Storing of sources of ?, e?, e
and of neutrons (Enlt14.5 MeV) during
simulation of the hadron cascade.55
9. Neutron transport (Enlt14.5 MeV) on the basis
of the28-groups ABBN neutron data library.
10. Analog and weighted simulation modes, open
architecture of the code
12
Modeling of inelastic hA- ? AA-interactions
(MSDM Multi Stage Dynamical Model)

• Fast, cascade stage of nuclear reaction
• DCM (Dubna Cascade Model ) 1
• Independent Quark-Gluon String Model (QGSM)
  2,3
• Coalescence model 1

Pre-equilibrium emission of nucleons and lightest
nuclei 4

• Equilibrium deexitation of residual nucleus
• Fermi break up of light nuclei 5
• Evaporation/Fission 5,6
• Multifragmentation of higly excited nuclei (SMM)
  7

1. V.D.Toneev, K.K.Gudima, Nucl. Phys. A400 (1983)
   173c.
2. N.S.Amelin, ?.?.Gudima, V.D.Toneev. Yad.Fiz. 51
   (1990) 1730 (in Russian).
3. N.S.Amelin, ?.?.Gudima, S.Yu.Sivoklokov,
   V.D.Toneev. Yad.Fiz. 52 (1990) 272 (in Russian).
4. K.K.Gudima, S.G.Mashnik, V.D. Toneev, Nucl. Phys.
   A401 (1983) 329.
5. A.S.Botvina, A.S.Iljinov, I.N.Mishustin et al.,
   Nucl. Phys. A475 (1987) 663.
6. G.D.Adeev, A.S.Botvina, A.S.Iljinov et al.
   Preprint INR, 816/93, Moscow, 1993.
7. Botvina, A.S. Iljinov and I.N. Mishustin,
   Nucl.Phys. A507 (1990) 649.

Cross sections of NA-, ?A- and
AA-interactions V.S.Barashenkov,
A.Polanski. Electronic Guide for Nuclear Cross
Sections. JINR E2-94-417, Dubna, 1994. Cross
sections of KA- ? NA-interactions
B.S.Sychev et al. Report ISTC, Project 187, 1999.
13
SHIELD-HIT (Heavy Ion Therapy) medical version
of the SHIELD. 1.Fluctuations of energy loss and
multiple Coulomb scattering are taken into
account. 2.Stopping power calculation dE/dx
according to ICRU49 (1993). 3.Detailed energy
grids for more precise interpolation of particle
ranges and cross sections. Track length
estimation of fluences of all particles in all
target zones. 5.Possibility to switch off
various physics processes etc.
Water target
Ion beam
?20?30 cm, step 1 mm
14
Comparison with experiment
15
Energy deposition into lead-uranium assembly
under irradiation by 1.5 GeV proton beam (The
Project EnergyTransmutation)
Integral energy deposition (MeV/proton)
SHIELD LAHET
Target 667 670
Blanket (total) Rod ?1 Rod ?2 Rod ?13 Rod ?14 583 26.9 30.8 10.9 14.6 607 28.1 33.0 11.0 14.6
Whole assembly 1250 1280
Target lead cylinder, size ?8.87???50??, mass
?35 ?? Blanket 30 rods ?3.6???20.8??, NatU in
aluminum envelop 0.5 mm, mass ?103 ??. Proton
energy 1.5 ???
16
Differential neutron yield from iron target
(10?10?20 ??) under irradiation by 1 GeV/u 238U
ion beam
17
Satellite Coronas
International Spase station (full configuration)
OS Mir
18
Proton and neutron fluxes in the Spectr module
of OA Mir under GCR 1996 irradiation
Neutron fluxes at Satellite Coronas, OS Mir
(the Cristall module) and at Airlock of ISS
under GCR 1996 irradiation.
Comparison of caculated and measured neutron
fluxes at OS Mir behind 20 g/cm2 Al depth at
solar max.