Hello I am looking to model a single gamma ray hit on a CdTe detector and measure the accumulated charge over pixels. My goal is to compare the amount of charged particles accumulated while adjusting the threshold.
I have noticed that the more events I simulated the larger the number of pixels were activated (an accumulation over all events). I am getting the behavior I expect in that the higher threshold lowers the spread of charge carriers, but I am not sure this is representative of a single gamma interaction.
Is there a way to average over each run the number of pixels activated and provide a better picture of what occurs in the detectors for a single gamma ray?
I was thinking of using the DepositionPointCharge module to generate equivalent number of charged particles in the detector and observe the propagation of the “induced” charge cloud, but I am not sure if that would work.
I appreciate any advice on the best way to approach my goal! Thank you
1keV Threshold
4keV Threshold
source_measurement.conf (1.1 KB)
detector.conf (123 Bytes)
minipix_tpx3_flex.conf (521 Bytes)
Hi @oobie2142
there are two options to select how many particles you simulate:
number_of_events this simulates multiple separate events, i.e. uncorrelated interactions with your detectornumber_of_particles in DepositionGeant4 this simulates multiple particles interacting with your detector simultaneiously.
/Simon
@simonspa So since the large distribution of charge was simulated with number_of_particles=1 and number_of_events_=100000 that is simulating a large amount of single gamma ray events and accumulating over each simulation run? It is just that this distribution seems larger than what I would expect. I would assume an initial charge cloud of approx 6um and a final interaction size of about 200um which is about 4 pixels in diameter.
Hi @simonspa,
Sorry for interrupt.
May I ask about this number_of_particles in DepositionGeant4 this simulates multiple particles interacting with your detector simultaneously.
I tried to increase this, but at some moment my running is killed and there are no results.
number_of_events = 1000
number_of_particles = 6000
Then, it “Killed” at the event (see the picture)
Do you have any idea how to tackle this issue?
I would say that your simulation parameters are not optimal yet.
You are running out of RAM.
/Simon
@simonspa Thanks Simon I will try again and see what I can change and report back. I have looked at the modules.root file to diagnose and have fixed the integration time. What are the other parameters that are typically adjusted when tuning a simulation? I do believe the geometry and detector config are setup as close as possible.
