N Beta Value in Full Axidal Model

kmjgod

Dear TOPAS users,

What value do we have to use for N Beta for Full Axial Model in TOPAS?
In TOPAS Technical Reference, N Beta value means;
" [axial_n_beta #20]: Define the number of rays emanating from a point X-ray source in the axial plane. Larger values for axial_n_beta increases both accuracy and calculation time."
We always use N Beta value "30" but I am not sure if I can increase this value.
Do we have any rules or a guide for setting up the N Beta value?

Thank you.

rowlesmr

I've never played with that value. Try it and see what happens. I'm guessing that values around 20-30 are good enough for most purposes.

kmjgod

Thank you for your comment. I applied the value "100" to the N beta, but no significant change occurred yet.
I will look into it further.

johnsoevans

You could try writing a little #list command that increments the value from 1 to 100 and simulate a pattern for each. That would give you an idea of the sensitivity of your peak shape to n_beta.