I’m collecting the energy inside a silicon ball of 5mm radius at the center of the world sphere → (I’m assuming here that I have to multiply the energy deposition by the weight of the particle.)
This detector is inside a sphere of aluminium with parameters (Rmin = 98mm, Rmax = 100mm)
I’m lacking of theory in Monte Carlo simulations. I’m certainly missing a normalisation factor due to the geometry, if that case, please tell me what i’m missing.
As far as I remember, that’s it. Well, you need particle type.
If you generate N particles, this is equivalent to a homogenous, isotropic fluence of N/(pi*R^2), where R is the radius of the cavity. The best explanation I know is something I wrote for a TOPAS example file, attached.
If I just accumulate the dose, I obtain a dose value far fewer than expected because only few particle goes through the detector. I feel I’m missing something which can statistically link the weighted spectrum I give as input and the energy deposition
It can be a very inefficient process. Only a few of the generated particles hit the component of interest. But it is reliable, i.e., no biases. I just hired hundreds of hours of CPU time.
There are other options. There is something called “Reverse Monte Carlo”, whereby you start close to the component, and estimate what a particle might have originated from. And I think this only works for electromagnetic processes. I’m not sure what the status is. All sounds a bit dodgy - perhaps others can enlighten us.
