How to plot axial distribution of spallation neutron

Dear @atsingan

Thank you for your thoughtfulness and sorry for lately reply, It seem like my input have a lot of mistake that I should check and fix it.

I have one question, I confuse the use of USRYIELD card. In my understanding, if I use region to region yielding, neutrons will be scored at surface boundary of the region. Please correct me.

But if I select yield: EMERGING as shown in picture, what position of neutron will be scored? Is it at the interaction or neutron emerging a while then will be scored somewhere in my geometry?

usryield

Thank you for your help,
Thanapong