[Gate-users] how to get proportionate number of photons detection

[Ashok Tiwari]

Dear GATE users,
 I tried to simulate the I-123 photons spectrum (a) using only 159 keV photon (83.3%) in one simulation and (b) all other high energy photons greater than 159 keV (~3%) in another simulation. 
In both of my simulations, I simulated a fixed number of primaries (decays) so that I could estimate the contribution of 159 keV and high energy photons separately. However, by defining the sources (see below), a similar number of photons have been detected in both simulations! This is undesirable as the intensity of their emissions are hugely different, as defined in the lines below. It looks like GATE normalized the intensity value (probability of emission); as a result of that, I may end up getting similar results for both simulations. Now, my question is, how can I define the sources in (b) to get a proportionate number of photons detection? If my assumption is right about normalization, is it possible to force GATE not to normalize the intensity values in (b)?

For (a) I define the following lines of code in my simulation settings:
/gate/source/addSource  src1            gps
/gate/source/src1/gps/particle            gamma/gate/source/src1/gps/energytype      Mono/gate/source/src1/gps/ene/mono        158.97 keV
/gate/source/src1/setIntensity             0.833/gate/source/src1/gps/angtype           iso/gate/source/src1/gps/type                 Point/gate/source/src1/gps/centre              0. 0. 0. mm/gate/source/src1/attachTo                 src_1/gate/source/list

For (b) I selected 5 major gamma emissions having energy greater than 159 keV:/gate/source/addSource  src1          gps/gate/source/src1/gps/particle          gamma/gate/source/src1/gps/energytype    Mono/gate/source/src1/gps/ene/mono      346.35 keV
/gate/source/src1/setIntensity           0.00125783/gate/source/src1/gps/angtype          iso/gate/source/src1/gps/type                Point/gate/source/src1/gps/centre             0. 0. 0. mm/gate/source/src1/attachTo                src_1
/gate/source/addSource  src2          gps/gate/source/src2/gps/particle          gamma/gate/source/src2/gps/energytype    Mono/gate/source/src2/gps/ene/mono      440.02 keV
/gate/source/src2/setIntensity          0.00428162/gate/source/src2/gps/angtype         iso/gate/source/src2/gps/type               Point/gate/source/src2/gps/centre            0. 0. 0. mm/gate/source/src2/attachTo               src_1
/gate/source/addSource  src3          gps/gate/source/src3/gps/particle          gamma/gate/source/src3/gps/energytype    Mono/gate/source/src3/gps/ene/mono      505.33 keV
/gate/source/src3/setIntensity          0.00315707/gate/source/src3/gps/angtype         iso/gate/source/src3/gps/type               Point/gate/source/src3/gps/centre            0. 0. 0. mm/gate/source/src3/attachTo               src_1
/gate/source/addSource  src4          gps/gate/source/src4/gps/particle          gamma/gate/source/src4/gps/energytype    Mono/gate/source/src4/gps/ene/mono      528.96 keV
/gate/source/src4/setIntensity           0.013911/gate/source/src4/gps/angtype         iso/gate/source/src4/gps/type               Point/gate/source/src4/gps/centre            0. 0. 0. mm/gate/source/src4/attachTo               src_1
/gate/source/addSource  src5          gps/gate/source/src5/gps/particle          gamma/gate/source/src5/gps/energytype    Mono/gate/source/src5/gps/ene/mono      538.54 keV
/gate/source/src5/setIntensity           0.00381514/gate/source/src5/gps/angtype         iso/gate/source/src5/gps/type               Point/gate/source/src5/gps/centre            0. 0. 0. mm/gate/source/src5/attachTo               src_1
Any help is highly appreciated. Thanks in advance.
Regards,Ashok 
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