Ernest Rutherford
Ernest Rutherford, 1st Baron Rutherford of Nelson, OM, FRS (30 August 1871 – 19 October 1937) was a New Zealand physicist who came to be known as the father of nuclear physics.Encyclopædia Britannica considers him to be the greatest experimentalist since Michael Faraday (1791–1867).
In early work, Rutherford discovered the concept of radioactive half-life, proved that radioactivity involved the nuclear 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", for which he is the first Canadian and Oceanian Nobel laureate, and remains the only laureate born in the South Island.
Rutherford moved in 1907 to the Victoria University of Manchester (today University of Manchester) in the UK, where he and Thomas Royds proved that alpha radiation is helium nuclei. 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 by the gold foil experiment of Hans Geiger and Ernest Marsden. He conducted research that led to the first "splitting" of the atom in 1917 in a nuclear reaction between nitrogen and alpha particles, in which he also discovered (and named) the proton.
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