The 3MW of used proton beam
One awkward issue is that most
optimisation studies have shown a small
angle (~0.1rad) is best for pion production
But in my optimisations the optimal angle
seems to be near zero!
This could be because the other studies
have looked at the pion yield closer to the
target and not downstream.
Tilting the rod could give a higher initial
yield but with a larger emittance