Ernest Rutherford

Ernest Rutherford, 1st Baron Rutherford of Nelson, (30 August 1871 – 19 October 1937) was a New Zealand physicist who was a pioneering researcher in both atomic and nuclear physics. Rutherford has been described as "the father of nuclear physics", and the greatest experimentalist "since Michael Faraday". In 1908, he was awarded the Nobel Prize in Chemistry "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances." He was the first Oceanian Nobel laureate, and the first to perform the awarded work in Canada. Rutherford's discoveries include the concept of radioactive half-life, the radioactive element radon, and the differentiation and naming of alpha and beta radiation. Together with Thomas Royds, Rutherford is credited with proving that alpha radiation is helium nuclei. In 1911, 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 performed the first artificially induced nuclear reaction in 1917 in experiments where nitrogen nuclei were bombarded with alpha particles. As a result, he discovered the emission of a subatomic particle which he initially called the "hydrogen atom," but later (more accurately) named the proton. Later, Rutherford capped off his exploration of the nucleus with the discovery of the neutron. He is also credited with developing the atomic numbering system alongside Henry Moseley. His other achievements include advances in radio communications and ultrasound technology. Rutherford became Director of the Cavendish Laboratory at the University of Cambridge in 1919. Under his leadership, the neutron was discovered by James Chadwick in 1932. In the same year, the first experiment to split the nucleus in a fully controlled manner was performed by students working under his direction, John Cockcroft and Ernest Walton.