To simulate the interaction of gamma photons with only oxygen (O) atom

[Marina123456]

Hello! i need help in such case. I want to simulate the interaction of gamma photons with only oxygen (O) atoms in MCNP, while am using the material card for silicon dioxide (SiO2). Which card shall I use to get the photon interacted with only the oxygen component separately. Thanks for help.

 

[Alex A]

Marina123456,
There are two ways of doing this that I know and I am unsure what you need. You can remove the Silicon from your material definition in the m card, and also reduce the density in the cell definitions for every use to account for the loss of the silicon. (d*32/60).

The other way prevents photonuclear processes with silicon with the mx card. This is in MCNP6+. If, for example, your silicon dioxide is m6 in your input file and silicon-28 is the first entry;

mx6:p z1=0

Ought to turn photonuclear processes off for silicon-28. (Turning things off does not work for any other process). I have never tried this!

So to be clear, these two methods do different things and I don't know what that means practically, it may depend on what you are trying to do. One takes entries on the m card out, the other turns off just photonuclear processes for selected entries on m cards.

 

[lucasfaraujo]

Hello! i need help in such case. I want to simulate the interaction of gamma photons with only oxygen (O) atoms in MCNP, while am using the material card for silicon dioxide (SiO2). Which card shall I use to get the photon interacted with only the oxygen component separately. Thanks for help.

Whats your MCNP version?