Deactivate does exactly what the OP was asking for
If the system is attached to an actor that gets destroyed, of course the component will get destroyed as well, killing all particles
If you absolutely want to destroy the actor, you can always detach the component, SetAutoDestroy to ensure that it dies when it’s complete, and deactivate it
But in most similar cases that I’ve encountered, the actor is usually “disabled” so no logic runs, and waits a bit for the effects to end
You can also use AActor::SetAutoDestroyWhenFinished, which will automatically destroy the actor when all latent actions and components on it are finished (by default all components except for Timelines, and effect components are finished allways)