18F(p,a): contaminants

The following figures show kinematic curves for a bunch of open reaction channels (results from Catkin) for 4.71 MeV 18(F,O,Ne) on CH2. I've considered proton scattering as well as (p,a) and (12C,p) and (12C,a). The most problematic reaction is 18Ne(p,a) because both the light and heavy products' kinematic curves lie almost on top of the 18F(p,a) curves; fortunately the Q values are quite different: +2882 keV for 18F vs. -6594 keV for 18Ne, so even if there is 18Ne present in the beam it may not produce any (p,a).