Ernest Rutherford, 1st Baron Rutherford of Nelson OM FRS was a New Zealand-born British chemist and physicist who became known as the father of nuclear physics. He is considered the greatest experimentalist since Michael Faraday.
In early work he discovered the concept of radioactive half-life, proved that radioactivity involved the transmutation of one chemical element to another, and also differentiated and named alpha and beta radiation. This work was done at McGill University in Canada. It is the basis for the Nobel Prize in Chemistry he was awarded in 1908 "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances".
Rutherford moved in 1907 to the Victoria University of Manchester in the UK, where he and Thomas Royds proved that alpha radiation was helium ions. Rutherford performed his most famous work after he became a Nobel laureate. In 1911, although he could not prove that it was positive or negative; he theorized that atoms have their charge concentrated in a very small nucleus, and thereby pioneered the Rutherford model of the atom, through his discovery and interpretation of Rutherford scattering in his gold foil experiment. He is widely credited with first "splitting the atom" in 1917 in a nuclear reaction between nitrogen and alpha particles, in which he also discovered the proton.