1. GAMOS tutorial Shielding Exercises
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
GAMOS tutorial Shielding Exercises
Pedro Arce Dubois
CIEMAT
Pedro Arce
Introducción a GEANT4
Andreas Pfeiffer, CERN/IT-API,

2. Shielding simulation Exercises
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Shielding simulation Exercises
Ex. 1: basic study of shield effect
Reduction factor of a shield
Effect of shield plate
Ex. 2: Shielding of an Am-Be source
Ex. 3: Flux and equivalent doses
Ex. 4: Activation studies
The exercises are sequential
Use the commands of the previous exercise (only change what indicated)
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 2

3. Exercise 1a: reduction factor of a shield
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Exercise 1a: reduction factor of a shield
Geometry: a plate of concrete (G4_CONCRETE) of surface 1 m X 1 m
Beam of 1 MeV neutrons along the positive Z axis hits the plate
QGSP_BIC_HP physics
Calculate the width of the plate so that only 1/10 of the neutrons traverse it
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 3

4. Exercise 1b: effect of shield plate
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Exercise 1b: effect of shield plate
Use the concrete shield defined in problem 1a
Make an histogram of the energy spectrum of neutrons and other types of particles that traverse the plate
i.e. exit the plate by the positive Z face
Store in a file the information of the particles that exit the shield by the positive Z face:
Event ID
track ID, particle name, energy, position X, Y & Z, direction theta & phi
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 4

5. Exercise 2a: Shielding of Am-Be source
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Exercise 2a: Shielding of Am-Be source
Place a point-like Am-Be source of 1 mCi inside a sphere of lead of inner radius 5 cm and outer radius 6 cm
Use the QGSP_BIC_HP physics list
Get the flux of neutrons and gammas that exit the sphere by the outer surface
Get the number of each type of interaction of the neutrons from the Am-Be source in the lead sphere
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 5

6. Exercise 3a: Flux and equivalent doses
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Exercise 3a: Flux and equivalent doses
Place a point-like Cf source of 10 mCi in the centre of a room of 8 X 8 X 8 m, with 20 cm of polyethylene cm of concrete walls, floor and ceiling
Use a concrete of density g/cm3 and composition:
Mg %
Mn %
O %
Al %
Pb %
H %
Cl %
Use the QGSP_BIC_HP physics list
Get the neutron flux as a function of energy at a point 10 cm after the room walls at the height of the source, and also the neutron personal equivalent dose, H* and ambient equivalent dose Hp(0,0)
Get the gamma flux as a function of energy and of the physics process that created the gamma at the same point
K %
Si %
Ca %
Na %
C %
Fe %
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 6

7. Exercise 4a: activation studies
Anaphe -- OO Data Analysis using C++ and Python
Anaphe -- OO Data Analysis using C++ and Python
January 17, 2011
January 17, 2011
Exercise 4a: activation studies
A beam of 18 MeV protons entering in a target of water enriched in 18O (100 %) to produce 18F
Beam shape has gaussian cylindrical profile of  = 5 mm
The proton source is at (0,0,0)
Water target
Cylinder of 1 cm radius and 5 cm length
Walls are 1 mm of copper
At entrance there is a circular aluminum window, 0.5 mm thick and radius 20 mm
Placed with axis along X, touching the source, extending in the positive X
Use as physics list QGSP_BIC_HP
Irradiate the target for 5 min
Calculate the activity of all isotopes produced
Calculate after 10 min more the dose at a point 10 cm apart from the front wall of the target
Pedro Arce
GAMOS radiotherapy tutorial
Andreas Pfeiffer, CERN/IT-API,
Andreas Pfeiffer, CERN/IT-API, 7