Ernest Rutherford wanted to look closer at ion-producing radiations. (He focused on Uranium, which he placed near a piece of foil and found some radiation deflect and the other goes right through the foil) (31 дек 1895 г. – 31 дек 1901 г.)

Labeled the two radiation parts Alpha (identical to a Helium nucleus) and Beta ( The same as an electron)

31 дек 1895 г.

31 дек 1901 г.

~ 6 years