Particle accelerator

To date, alpha particles were the most readily available to study, along with cosmic rays which were outside of human control. The particle accelerator uses a voltage multiplier and electromagnet to accelerate protons to high energy levels. This innovation allowed to manufacture energetic particle collisions on demand.
 John Douglas Cockcroft, Ernest Thomas Sinton Walton England 1929 Particle accelerator

To date, alpha particles were the most readily available to study, along with cosmic rays which were outside of human control. The particle accelerator uses a voltage multiplier and electromagnet to accelerate protons to high energy levels. This innovation allowed to manufacture energetic particle collisions on demand.