Beam scanning source

Dear FLUKA expert,
For the electron accelerator, the circular beam emits at an angle of about 60° in the x-direction and 3° in the y-direction. In the beam parameter setting, there is a divergence type, but it seems to be set to the same emission angle in all directions. How can I set the parameters to solve this problem?
Looking forward to your reply, thanks!
Jushigang Yuan

Dear Jushigang Yuan,

you could use a BEAMSPOT source option of SPECSOUR. The associated SPOTBEAM card allows to enter separate divergence angles for the two axes.
See slide 25+ from https://indico.cern.ch/event/1123370/contributions/4716094/attachments/2448156/4195155/19_Advanced_sources_2022_ULB.pdf

Alternatively, you could take a look at the source_newgen.f user routine, which also allows different divergence angles.

Cheers,
David