In the 1911 Rutherford gold-foil experiment, what did most alpha particles do when fired at thin gold foil?

In the 1911 Rutherford gold-foil experiment, most alpha particles passed straight through the thin gold foil.

Ernest Rutherford directed alpha particles at a very thin sheet of gold and measured where they went. Nearly all traveled through with little or no deflection, while a small fraction changed direction sharply. A very tiny number rebounded toward the source.

The result overturned the earlier “plum pudding” model, which pictured positive charge spread throughout the atom. Rutherford concluded that an atom is mostly empty space, with almost all its positive charge and mass concentrated in a tiny central nucleus. Electrons occupy the surrounding region.

Hans Geiger and Ernest Marsden carried out the scattering work under Rutherford’s direction. The famous experiment is often called the gold-foil experiment, although the broader evidence came from measuring many alpha-particle trajectories and their deflection angles.