Monoenergetic proton pencil beam

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Line 113: Line 113:
</pre>
</pre>
 +
The corresponding '''PlotDose.txt''' is:
-
Open Proton.root file in the following way:
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<pre style="color: #800000; background-color: #dcdcdc">
 +
1.33333 20.404
 +
2.66667 20.8104
 +
4 21.384
 +
5.33333 21.6998
 +
6.66667 22.2678
 +
8 22.7073
 +
9.33333 23.277
 +
10.6667 23.8187
 +
12 24.4422
 +
13.3333 25.0271
 +
14.6667 26.2448
 +
16 26.9606
 +
17.3333 27.7964
 +
18.6667 29.2873
 +
20 30.4008
 +
21.3333 32.1977
 +
22.6667 33.636
 +
24 35.6517
 +
25.3333 38.9188
 +
26.6667 42.4489
 +
28 47.8598
 +
29.3333 56.5847
 +
30.6667 75.3499
 +
32 100
 +
33.3333 4.58297
 +
34.6667 0
 +
36 0
 +
37.3333 0.00102844
 +
38.6667 0
 +
40 0
 +
</pre>
 +
 
 +
=== <span style="color:#000080"> Root file </span> ===
 +
 
 +
Open '''Proton.root''' file in the following way:
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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</pre>
</pre>
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Inside is 1D histogram showing the energy deposition in water box:
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<span style="color:#000080"> '''This is the energy deposition along the beam in the absorber:''' </span>
 +
 +
http://www.hep.ucl.ac.uk/pbt/RadiotherapyWorkbook/skins/common/images/ProtonPB/BraggPeak_PB.png
 +
 +
<span style="color:#000080"> '''This is the energy deposition along the beam in the absorber, zoomed around the peak:''' </span>
 +
 
 +
http://www.hep.ucl.ac.uk/pbt/RadiotherapyWorkbook/skins/common/images/ProtonPB/BraggPeak_PBzoom.png 
 +
=== <span style="color:#000080"> Changes in proton.mac </span> ===
You can change the physics process, incident proton energy and number of slices etc. by
You can change the physics process, incident proton energy and number of slices etc. by
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/protonPB/det/setSizeX  4 cm
/protonPB/det/setSizeX  4 cm
/protonPB/det/setSizeYZ 4 cm
/protonPB/det/setSizeYZ 4 cm
-
/protonPB/det/setSliceSizeYZ 2 cm
+
/protonPB/det/setSliceSizeYZ 1 cm
-
/protonPB/det/sliceNumber 12
+
/protonPB/det/sliceNumber 30
#
#
# set physics process
# set physics process
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# production tresholds (recommended range  
# production tresholds (recommended range  
#cut off not bigger than 10% of slice thickness)
#cut off not bigger than 10% of slice thickness)
-
/protonPB/phys/setCuts 0.5 mm
+
/protonPB/phys/setCuts 0.2 mm
#/protonPB/phys/setGCut 1 um
#/protonPB/phys/setGCut 1 um
#/protonPB/phys/setECut 1 um
#/protonPB/phys/setECut 1 um
Line 172: Line 215:
# step limit (recommended not bigger than 5% of  
# step limit (recommended not bigger than 5% of  
# slice thickness)
# slice thickness)
-
/protonPB/stepMax 0.2 mm
+
/protonPB/stepMax 0.1 mm
#
#
/protonPB/event/printModulo 50
/protonPB/event/printModulo 50
Line 186: Line 229:
</pre>
</pre>
-
=== Change the physics process ===
+
'''Change the physics process'''
The default physics process is '''QGSP_BIC_EMY'''. This is a physics list recommended for proton therapy. You can check what will be the dose deposition if you change the physics list. In proton.mac change
The default physics process is '''QGSP_BIC_EMY'''. This is a physics list recommended for proton therapy. You can check what will be the dose deposition if you change the physics list. In proton.mac change
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</pre>
</pre>
-
=== Change the incident particle energy ===
+
'''Change the incident particle energy'''
The default energy is 62 MeV. This is one of the energies used in radiotherapy. In proton.mac you can change the value of 62 MeV  
The default energy is 62 MeV. This is one of the energies used in radiotherapy. In proton.mac you can change the value of 62 MeV  
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</pre>
</pre>
-
=== Change the number of slices ===
+
'''Change the number of slices'''
-
You can change the number of water box slices. The default number is 12. Keep in mind that  
+
You can change the number of slices. The default number is 30. Keep in mind that  
-
if you want to have more slices you need to modify the file DetectorConstruction.hh in
+
if you want to increase the number of slices you need to modify the file DetectorConstruction.hh in
/ProtonPB_source/include/.
/ProtonPB_source/include/.
-
In DetectorConstruction.hh change the MaxLayer to a value which is bigger or equal to the
+
In DetectorConstruction.hh set MaxLayer to a value which is bigger than the
-
number of your slices.
+
number of your slices. The default value is 40. For example, if you want to have 35 slices you do
 +
not need to modify MaxLayer. Then in proton.mac change the number of slices
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
-
const G4int MaxLayer = 10;
+
/protonPB/det/sliceNumber 35
</pre>
</pre>
-
Then in gamma.mac you need to change the number of slices
+
then run the macro
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
-
/protonPB/det/sliceNumber 10
+
./protonPB proton.mac
</pre>
</pre>
-
You modified the code therefore you need to comppile it again. In directory PhotonPB_build do
+
If you modify the files in ProtonPB_source (for example change the value of MaxLayer) you need to comppile the code again. In directory PhotonPB_build do
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">

Revision as of 10:49, 22 July 2014

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