According to someone much smarter then me "The incoming Gold Ion [Cosmic Ray], being ‘charged’, would be SIGNIFICANTLY affected/slowed by the randomly oriented charge flux in Earth/Atmospheric matter environment LONG before it finally ‘collides’ with any particular planet-sourced ion."
In general, I'd warn people not to be taken in by the frenzy of "OHMIGOD THE EARTH WILL BE DESTROYED" stuff on the internet in the months and weeks leading up to when this is turned on - I expect a lot of the usual suspect Apocalyptikook websites will go nuts over this.