[Gate-users] Interpretation of volumeID variable in root file in optical simulation

[Paweł Kowalski]

Hello,

Thanks to help of Vesna, I have solved the problem of lack of
coincidences in the results of my simulations.
In short: GATE works properly, there was an error in my code used for analysis.

> I have a question about volumeID variable.
>
> In my simulation I have a system of two plastic scintillating strips. At
> both ends of each strip, there are photomultipliers.
>
> System looks like that:
>
> PMT1==========PMT2 - strip with two PMTs
>
>                   S           - point source of back-to-back gamma in the
> middle of the system
>
> PMT3==========PMT4
>
> In my case, coincidence is a situation when I have optical photons at each
> of 4 photomultipliers at both strips.
>
> When I analyze root output, I check if in single event there were hits with
> different volumeID[1]. Unfortunately for each event volumeID[1] has the same
> value for all hits so it gives me no coincidences.

The problem was, the way that I used volumeID variable. I wasn't
reading this variable properly. It was a programming error.

Best regards,
Paweł Kowalski,
National Centre for Nuclear Research,
Świerk Computing Centre