3D Rutherford Gold Foil Scattering

Fire α particles at a gold nucleus and observe Coulomb scattering in 3D.

α particle Au nucleus Gold foil
Drag • Wheel • Pinch

About the experiment

Most α particles pass through — the atom is mostly empty space. Large-angle scattering proves a tiny, dense, positively charged nucleus.

Scattering angle rises with nuclear charge Z and falls with particle kinetic energy.