Regarding simulation of the effect of increasing MOT beam size on Steady-state captured atom number

[Seen Alif]

I am working on Rb-87 atom and want to simulate the structure and see the effect of steady-state atom number as MOT laser beam size increases. I want to check if the 'N' scales with 'D^4' or not. Any suggestions would be appreciated. I have written a code using pylcp. If needed, I will share the code too. 

Thank you