The Vinca Institute of Nuclear Sciences

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The Vinca Institute of Nuclear Sciences Belgrade,
Serbia
INTERCOMPARISON OF THE USAGE OF COMPUTATIONAL
CODES IN RADIATION DOSIMETRY Bologna, Italy, July
14-16 2003
P3. Dose distribution of a proton beam in water
phantom calculated by SRNA-2KG code
http//www.nea.fr/
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A parallel beam of protons from a disk source
(diameter 15 mm) impinges on a PMMA compensator
(cylindrical symmetry) and on a spherical water
phantom approximating an eye (figure 1). All
elements are in vacuum. If discrete regions are
used for dose calculations (depth-dose and
isodose curves), use voxels with dimensions 0.5 x
0.5 x 0.5 mm3. The results should be normalized
to one primary proton
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NUMERICAL EXPERIMENTS BY SRNA-2KG CODE
The SRNA-2KG is a Monte Carlo code for use in
proton transport, radiotherapy, and dosimetry.
Protons within an energy range of 100 keV to 250
MeV with pre-specified spectra are transported in
a 3D geometry through material zones confined by
planes and second order surfaces or in 3D
voxelized geometry. The simulation of proton
transport is based on the multiple scattering
theory of charged particles and on a model for
compound nucleus decay. For each part of the
range, an average loss of energy is calculated
with a fluctuation from Vavilovs distribution.
The deflection angle of protons is sampled from
Moliere distribution.
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• SRNA-2KG code attributes
• Physical model is theoretically consistent
• for 3D Monte Carlo numerical experiments
• Comprehensive for dosimetry and proton therapy
• Works in 3D combined and 3D voxelized
• medium and source geometries
• Linux or Windows Fortran 77 source code
• and libraries on one floppy 3.5

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Part 1/1 50 MeV monoenergetic proton beam
Depth-dose distribution in spherical phantom
along the diameter D parallel to the proton beam
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Part 1/2a 50 MeV monoenergetic proton beam
Isodose curves on the equatorial plane of the
water phantom parallel to the proton beam
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Part 2/1 Effect of a beam modulator by sampling
discrete energies from spectra (40-50) MeV with
weights
Depth-dose distribution in spherical phantom
along the diameter D parallel to the proton beam
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Part 2/2a Effect of a beam modulator by
sampling energies from discrete spectra (40-50)
MeV
Isodose curves on the quatorial plane of the
water phantom parallel to the proton beam
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Part 2/1 Effect of a beam modulator by sampling
energies from spectra (40-50) MeV with weights
Depth-dose distribution in spherical phantom
along the diameter D parallel to the proton beam
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Part 2/2a Effect of a beam modulator by
sampling energies from spectra (40-50) MeV with
weight.
Isodose curves on the equatorial plane of the
water phantom parallel to the proton beam.