[Gate-users] noise issues

[Devin VanElburg]

Hello Gate users,

I am having an issue with noise. When I define my energy and deltaT distributions and add noise to my digitizer, my simulation crashes. I found that if I set my deltaT to a very high number with respect to my simulation time length (in this case 1s), my simulation will run, but very slowly. Furthermore, there is no added noise in my output. Why does the addition of noise slow down the simulation so much? This is how I have it defined as of now:

/gate/distributions/name energy_distrib
/gate/distributions/insert Gaussian
/gate/distributions/energy_distrib/setMean 400 keV
/gate/distributions/energy_distrib/setSigma 0 keV

/gate/distributions/name dt_distrib
/gate/distributions/insert Exponential
/gate/distributions/dt_distrib/setLambda 1000 s

/gate/digitizer/Singles/insert noise
/gate/digitizer/Singles/noise/setDeltaTDistribution dt_distrib
/gate/digitizer/Singles/noise/setEnergyDistribution energy_distrib


I set the energy sigma to 0 so any 400keV Singles would be the result of noise and not my source. If I set lambda to be 100s or less, my computer freezes up. When I comment out the above lines, my DAQ takes less than a second and generates around 90 entries at the 511keV range.

Can anyone help me out? Am I defining my distributions wrong? Surely these parameters should not slow down DAQ so incredibly much, especially if they're not even generating any entries into the output. 

I appreciate the help!
Devin Van Elburg

---------------------
Lakehead University
Physics w/ c/ Biomedical Physics

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