Scoring the number of deposits with energy

Dear FLUKA experts,

I have to work on counting the number of deposits between certain energies (10keV to 200keV) within a certain region.
The primary particles are neutrons, but the final depositing particles do not need to be distinguished.
I found 3 cards(USRBIN, SCORE, DETECT) related to energy deposition, but these seem to differ slightly from my work.
I need two things. One is the total number of deposits (number of hits) and the energy of each deposition.

please give me any advice.

Dear @logan12,

I am not sure that I understand what you need to achieve.

First, when scoring energy deposition in FLUKA, this is done in a continuous manner along the particle track, not by taking into account individual collisions (this is what is called “condensed particle history” in a Monte Carlo simulation).
Second, does your study take into account only ionizing energy losses or also non-ionizing energy losses? Since you are using neutrons as primary particles, the energy deposition will indeed be due to the secondaries resulting from inelastic interactions.

It seems from your explanation that perhaps it is actually the inelastic events which you want to count? For this the SCORE card is indeed an option, this way you can count the amount of events since you score the “star” density, i.e. the density of hadronic inelastic interactions above a certain threshold. Also if you don’t want to distinguish the “final depositing particles”, how do you want to calculate the energy deposition of each deposition?

Before I can give more advice please further clarify what you need to achieve.



Dear Andreas,

I understand your first answer, but unfortunately I have to consider individual collisions. If this is not possible, or very difficult, we should probably change our simulation plan.

To answer your second and remaining questions, I first show you the simulation geometry.

This simulation is to calculate the background by giving similar conditions under which the actual background occurs. Therefore, what we are trying to see is the number of energy deposition within the signal region (10 ~ 200keV) inside the CsI crystal. That’s why I said we don’t have to know which particles are depositing. Likewise, it doesn’t matter which process deposits the energy. (However, it would be very useful to know these informations for the next step.)

And I’ve already used the SCORE card to get results with the same geometry.

(region1 is the CsI crystal)
If this were the total number of inelastic interactions caused by neutrons, this would be useful, but since there is no information about the energy and other interactions, it is very scarce.

If each collsion is saved for each event, it seems that the total number of collisions is obtained by adding the results obtained for each event.

Then, is it impossible to obtain the number of depositions and each deposited energy caused by all kinds of interactions with FLUKA simulation?


Hello @logan12 ,

In case you are simply interested in getting the energy deposition distribution, irregardless of what primary or secondary particle triggered it, it suffices to use the DETECT card and set the energy limits to the signal range you indicated (10 to 200keV). Using the same simulation, simply count the amount of inelastic events by indeed looking at the star density (and taking into account the volume of the regions which you need to calculate yourself).

The total number of collisions can indeed be obtained by adding all the events, also considering different simulations runs. Of course here you need to take into account the amount of primary particles you simulated, hence you need the neutron fluence that you want to scale your results to.

For the inelastic collisions and subsequent processes which you would like information on, I would advise you to look at this and this on the use of mgdraw.f, in addition to the manual, particularly the entries ENDRAW (for energy deposition events) and USDRAW (selecting inelastic collisions by using ICODE=101). In case you want to select only events caused by neutrons you need to select JTRACK.EQ.8. It is up to the user to then customize the routine to ask for more desired information.

Hope this helps,