Monoenergetic photon pencil beam

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water box along the beam line. It also produces text files: '''DoseFile.txt''' with  
water box along the beam line. It also produces text files: '''DoseFile.txt''' with  
energy and dose deposited in each slice and '''PlotDose.txt''' with dose deposited in each slice.  
energy and dose deposited in each slice and '''PlotDose.txt''' with dose deposited in each slice.  
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This is an example output with the default settings: physics process emstandard_opt0 and incident gamma energy of 20 MeV.  
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=== <span style="color:#000080"> Text files </span> ===
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This is an example output for '''DoseFile.txt''' with physics process '''emstandard_opt0''' and incident photon energy of '''20 MeV'''.
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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  MaxDose is the highest dose value from all slices.
  MaxDose is the highest dose value from all slices.
</pre>
</pre>
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This is PlotDose.txt. These values can be directly imported in matlab.
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<pre style="color: #800000; background-color: #dcdcdc"> 
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10 32.1047
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20 50.0432
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30 62.3066
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40 77.3614
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50 80.9917
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60 89.7831
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70 99.7318
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80 100
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90 95.7783
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100 95.3955
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110 93.4478
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120 91.2579
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130 90.4998
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140 87.7295
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150 90.0244
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160 88.9634
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170 80.4985
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180 79.051
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190 77.9945
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200 0
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</pre>
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=== <span style="color:#000080"> Root file </span> ===
Open Gamma.root file in the following way:
Open Gamma.root file in the following way:
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Select ROOT files and Gamma.root
Select ROOT files and Gamma.root
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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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The histogram inside Gamma.root shows the energy deposition in water box:
   
   
http://www.hep.ucl.ac.uk/pbt/RadiotherapyWorkbook/skins/common/images/PhotonPB/Edep_PhotonB.png  
http://www.hep.ucl.ac.uk/pbt/RadiotherapyWorkbook/skins/common/images/PhotonPB/Edep_PhotonB.png  
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=== <span style="color:#000080"> Changing macro gamma.mac </span> ===
You can change the physics process, incident photon energy, phantom material, number of slices etc. by
You can change the physics process, incident photon energy, phantom material, number of slices etc. by
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</pre>   
</pre>   
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This is what you will see:
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This is the content of the macro:
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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#
#
# number of events
# number of events
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/run/beamOn 10000
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/run/beamOn 6000
</pre>
</pre>
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=== Change the physics process ===
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'''Change the physics process'''
The default physics process is '''emstandard_opt0'''. This package is used in high energy experiments. In gamma.mac change
The default physics process is '''emstandard_opt0'''. This package is used in high energy experiments. In gamma.mac change
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</pre>
</pre>
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=== Change the incident particle energy ===
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'''Change the incident particle energy'''
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The default energy is 20 MeV. This is one of the energies used in radiotherapy. In gamma.mac you can change the value of 20 MeV  
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The default energy is 20 MeV. It is a typical energy used in radiotherapy. In gamma.mac you can change the value of 20 MeV  
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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means that only one particle is generated, incident from (x0,y0,z0). The default number of
means that only one particle is generated, incident from (x0,y0,z0). The default number of
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events is set to 10000. Therefore, 10000 particles are incident to the water box.  
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events is set to 6000. Therefore, 6000 particles are incident to the water box.  
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=== Change the material of the phantom ===
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'''Change the material'''
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This example is to compute the energy deposition of photons in a water box. However,
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In this example we compute the energy deposition of photons in water box. However,
there is an option to change the box material from water to lead.  
there is an option to change the box material from water to lead.  
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</pre>
</pre>
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=== Change the number of slices ===
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'''Change the number of slices'''
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You can change the number of water box slices. The default number is 20. Keep in mind that  
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You can change the number of slices. The default number is 20. Keep in mind that  
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if you want to have more slices you need to modify the file DetectorConstruction.hh in
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if you want to have bigger number of slices you need to modify the file DetectorConstruction.hh in
/PhotonPB_source/include/.
/PhotonPB_source/include/.
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In DetectorConstruction.hh change the MaxLayer to a value which is bigger or equal to the
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In DetectorConstruction.hh set MaxLayer to a value which is bigger then the number of your slices. The default number is MaxLayer=30. For example, if you want your box to be divided to 35 slices you need to set the value of MaxLayer to ,for example, 40 then in gamma.mac you need to change the number of slices:
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number of your slices.
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<pre style="color: #800000; background-color: #dcdcdc">
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const G4int MaxLayer = 30;
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</pre>
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Then in gamma.mac you need to change the number of slices
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<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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/photonPB/det/sliceNumber 30
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/photonPB/det/sliceNumber 35
</pre>
</pre>
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You modified the code therefore you need to comppile it again. In directory PhotonPB_build do
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Every time you modify files in PhotonPB_source you need to compile your code again. In directory PhotonPB_build do
<pre style="color: #800000; background-color: #dcdcdc">
<pre style="color: #800000; background-color: #dcdcdc">
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</pre>
</pre>
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=== <span style="color:#000080"> Visualisation </span> ===
== <span style="color:#000080"> Files </span> ==
== <span style="color:#000080"> Files </span> ==
[[List of files with brief description]]
[[List of files with brief description]]

Revision as of 12:01, 22 July 2014

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