Geant4-based simulations of microdosimetric data
for high charge and energy particles
Lucas Burigo1
in colaboration with
Igor Pshenichnov, Igor Mishustin,
Marcus Bleicher
1 Frankfurt
Institute for Advanced Studies - FIAS
Johann Wolfgang Goethe-University
) [email protected]
9th Geant4 Space Users’ Workshop, Barcelona, March 4-6, 2013
Space Radiation
Radiat Environ Biophys (2012) 51:245–254
253
tissues and materials. However, their quantification and
implications in radiation protection and RHA require
further research in a case-by-case approach. It is concluded that the methodologies described in the present
paper can be developed in the future for exploring these
effects and their implications to RHA and radiation
protection.
Acknowledgments The authors would like to acknowledge the
support and interest of all members of the ESA Component Space
Evaluation and Radiation Effect Section and to all members of ESA
Space Environment and Effects Section for the fruitful discussions
and test data collected at GANIL. This work was funded by the
Portuguese Foundation for Science and Technology and by the
European Space Agency.
Fig. 10 Spectrum of galactic cosmic radiation (GCR) ions (from
hydrogen
to nickel)
on near-Earth
interplanetary/geosynchronous
Source:
A. Keating
et al.,
2012
orbit. This spectrum was calculated for solar maximum using
CREME2009 that is an extension of CREME96 code (Tylka et al.
1997) including Nymmik model (Mendenhall and Weller 2012).
Symbols mark the most abundant ions of hydrogen, helium, carbon,
nitrogen, oxygen and iron
Source: M. Durante and F. Cucinotta, 2008
References
S, Allisonions
J, Amakocontribute
K, Apostolakis J, Araujo
H, Arce P,
Detected particles from galactic Agostinelli
Several
differently
Asai M, Axen D, Banerjee S, Barrand G, Behner F, Bellagamba
L, Boudreau J, Broglia L, Brunengo A, Burkhardt H, Chauvie S,
cosmic rays (GCR) consist of 83% to
absorbed dose. Shielding is a
Chuma J, Chytracek R, Cooperman G, Cosmo G, Degtyarenko P,
Dell’Acqua A, Depaola G, Dietrich D, Enami R, Feliciello A,
simulation of different devices for different SEE types in
protons, 14% helium and 1%
problem
due
to G,high
high
Ferguson C, Fesefeldt
H, Folger
Foppianocharge
F, Forti A, Garelli
support to RHA guidelines development.
S, Giani S, Giannitrapani R, Gibin D, Gómez Cadenas JJ,
heavier nuclei. The maximum of
energy
(HZE)
particles.
González I, Gracia
Abril G, Greeniaus
G, Greiner W, Grichine
V, Grossheim A, Guatelli S, Gumplinger P, Hamatsu R,
the spectrum for specific nuclei is Hashimoto K, Hasui H, Heikkinen A, Howard A, Ivanchenko
Conclusions
V, Johnson A, Jones FW, Kallenbach J, Kanaya N, Kawabata M,
Kawabata Y, Kawaguti M, Kelner S, Kent P, Kimura A, Kodama
between
100-1000
The
results presented
here showMeV/u.
that radiation-induced
T, Kokoulin R, Kossov M, Kurashige H, Lamanna E, Lampén T,
effects on electronic devices intrinsically depend both on
Lara V, Lefebure V, Lei F, Liendl M, Lockman W, Longo F,
Magni S, Maire M, Medernach E, Minamimoto K, Mora de
Radiation Effects by Ions (I)
Carbon ions of ∼300 MeV/u are
successfully applied in cancer
therapy.
Source: NASA
Source: HIT
Irradiation by ions from GCR is
the major concern for human
exploration at space.
Better understanding of radiation effects due to ion tracks are required
for ion beam cancer therapy and interplanetary human missions.
Radiation Effects by Ions (II)
9.5 MeV/u
12
C by in-beam microscopy.
Source: B. Jakob et al., 2009
Single strand
breaks are usually
repaired by the
cell.
It is more difficult
to repair double
and multiple
strand breaks.
Energy imparted to tissue per unit of track length on scale of
micrometres and nanometres matters to the biological action of radiation.
Microdosimetry Technique
Patterns of energy deposition on micrometer scale are measured by
means of a Tissue-Equivalent Proportional Counter (TEPC).
Scheme of a typical
walled TEPC
Lineal energy: y = ε/l¯
ε: energy deposited in the TEPC
l¯ = 23 d: mean chord length
TEPC is commonly flown on the
ISS. TEPC is also applied for
investigation of radiation effects at
ground-based facilities.
TEPC: a plastic sphere filled
with low-pressure gas, equivalent
to a few µm sphere of tissue, an
object of a cell nucleus size.
Monte Carlo simulations can be
applied to investigate different
scenarios of particle/energy/target
in space.
Monte Carlo Model for Investigation of Radiation Effects
The Monte Carlo model for Heavy-Ion Therapy (MCHIT) was
developed at FIAS for benchmarking of Geant4 models to
experimental data relevant to ion beam cancer therapy.
MCHIT was extended for benchmarking of models to experimental
data relevant to space research as well.
Detailed implementation of TEPCs are applied for simulation of
microdosimetric data for HZE particles.
Wall-less
TEPC
MCHIT@FIAS
Walled TEPC
Characterization of TEPC at HIMAC and AGS
Experimental characterization of TEPC was performed at HIMAC and
AGS with several ion beams in the energy range of 200-1000 MeV/u.
Experimental scheme
PSD detectors were used to
evaluate impact parameter b
and rule out events due to
beam fragments.
Experimental data can be used for benchmarking of electromagnetic
models. G4EmStandard opt3 (EmStd) and G4EmPenelope (EmPen)
were used with threshold for production of δ-electrons set to 1 keV
and 100 eV, respectively.
f (ε)
Response Function of TEPC
The wall effect is reproduced by
both set of electromagnetic
models.
56
Fe 360 MeV/u
Si 780 MeV/u
20
Ne 210 MeV/u
EmPen
EmStd
0.1
28
b < 0.5 mm
x2
b < 0.8 mm
ε (keV)
0.05
gas
wall
grazing event
200
0
0
100
200
ε (keV)
x3
The distribution of events for
Ne and Si ions in central
crossing of the detector are well
reproduced. Energy deposition
is overestimated for Fe ions.
100
56
Fe 360 MeV/u
20
Ne 210 MeV/u
EmPen
EmStd
0
0
2
4
6
b (mm)
Source: L. Burigo et al., 2013
TEPC Inside a Phantom at GSI
Irradiation by 185A MeV 7 Li and 300A MeV
y d(y)/ ion
Source: G. Martino et al., 2010
10
0 cm, plateau
0 cm, peak
data
EmPen/HadQMD
1
1
0 cm, tail
10-2
C
B
10-1
10-1
Be
10-3
Li
He
10-2
10-2
H
10-4
10-3
10-3
10-4
10-5
2 cm, plateau
2 cm, peak
10-2
2 cm, tail
10-2
10-3
10-3
10-3
10-4
10-4
10-4
10-5
10 cm, plateau
10 cm, peak
10-4
10 cm, tail
10-4
10-5
10-5
10-5
10-6
10-6
10-6
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
12 C
pencil-like beams.
TEPC Measurements at Several Positions (I)
12
y d(y)/ ion
Spectra on beam
axis are mainly due
to primary ion and
heavy fragments.
C 300 MeV/u
10
0 cm, plateau
0 cm, peak
data
EmPen/HadQMD
1
1
B
10-1
10-1
Be
10-3
Li
He
-2
10
10-2
Only protons and
neutrons contribute
far from the beam
axis.
0 cm, tail
10-2
C
H
10-4
10-3
10-3
-4
10
10-5
2 cm, plateau
2 cm, peak
10-2
2 cm, tail
10-2
10-3
10-3
10-3
10-4
The contribution of
secondary neutrons
to the out-of-field
dose from 12 C beams
amounts to about
50% of the total far
from the beam.
10-4
10-4
10-5
10 cm, plateau
10 cm, peak
10-4
10 cm, tail
10-4
10-5
10-5
10-5
10-6
10-6
10-6
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
Source: L. Burigo et al., 2013
TEPC Measurements at Several Positions (II)
Hadronic models are
not able to describe
the measurements
for 7 Li beam.
y 2 f(y) /ion
7
Li 185 MeV/u
10
0 cm, plateau
0 cm, peak
data
10
0 cm, tail
EmPen/HadQMD
10-2
EmPen/HadBIC
1
1
-1
10
10-3
-1
10
-2
10
10-2
10-4
There is still room
for major
improvements of
Geant4 models
describing
propagation of 7 Li
nuclei in water.
2 cm, plateau
10-2
2 cm, peak
2 cm, tail
10-2
10-2
10-3
10-3
10-3
10-4
10-4
10 cm, plateau
10 cm, peak
10 cm, tail
10-4
10-4
10-5
10-5
10-5
10-6
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
10-1
1
10
102
3
10
y (keV/µ m)
Source: L. Burigo et al., 2013
H
ge
1 a
)
He
Si
Microdosimetry with Wall-Less TEPC at HIMAC (I)
1
4
1
2
14
160
150
490
0.52
2.2
28
55
Fig. 1. Photographs of the wall-less TEPC, (a) the overview, (b)
the detection a
partrange
and (c) the field
tube. unit [mm].
Wall-less TEPC behind
shifter
irradiated by H, He and Si ions.
lculated by ATIMA.
He and Si Ions
265
Wall-less TEPC behind a rage shifter.
Measurements are sensitive to nuclear
reactions.
Experimental set-up in HIMAC-BIO (not in scale). The collimated size of the incident beams on
S. Tsuda et al., 2012
l-less TEPC is approximately 100 mm inSource:
diameter.
y f(y)/ y
F
1
10-1
Internal geometry of
wl-TEPC in MCHIT
10-2
wl-TEPC behind
a range shifter
of 163 mm-we
Calculated microdosimetric spectra
for protons behind a range shifter
with wall-less TEPC agree well with
experimental data.
10
-3
1
H 160 MeV
EmPen/HadBIC
10-4 -1
10
1
10
102
y (keV/µm)
Source: L. Burigo et al., 2013
Microdosimetry with Wall-Less TEPC at HIMAC (II)
y f(y)/ y
F
1
4
10-1
He 150 MeV/u wl-TEPC behind
EmPen/HadBIC
a range shifter
Z=2
of 157.1 mm-we
Z=1
e-
Simulations with hadronic
models BIC and QMD present
similar results.
10
10-1
y f(y)/ y
F
10-2
-3
10-2
10-4 -1
10
1
10
102
y (keV/µm)
Disagreement at low y may be
related to underestimation of
yield of hydrogen-like fragments
produced in nuclear reactions of
helium ions.
10
-3
28
10-4
Si 490 MeV/u
EmPen/HadBIC
wl-TEPC behind
a range shifter
EmPen/HadQMD of 159.3 mm-we
10
-5
1
10
102
10
y (keV/µm)
Source: L. Burigo et al., 2013
3
Conclusions
Methods used to simulate detectors in nuclear and particle physics
experiments are also successful for calculation of patterns of energy
deposition on micrometre scale.
With G4/MCHIT model one can calculate microdosimetric data for
many ions and beam energies relevant for ion beam cancer therapy
and space research.
Microdosimetric spectra are equally well described by Geant4
electromagnetic models EmStandard opt3 and EmPenelope.
Measurements with TEPC inside or behind a phantom impose a
challenge for hadronic models. Geant4 models are able to describe
reasonably well microdosimetric spectra in the presence of nuclear
fragmentation reactions.
Further developments of nuclear fragmentation models for helium
and lithium nuclei could improve the description of the
microdosimetric data.
Thank you for your attention!
Thanks to the Organizing Committee.
I am grateful to the
Beilstein Institute
for support.
Many thanks to
Igor Mishustin
Igor Pshenichnov
Marcus Bleicher