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Ernest T. S. Walton Irish physicist Ernest T. S. Walton won the 1951 Nobel Prize in physics. He invented the particle accelerator and was the first to split atoms and to successfully
Ernest T. S. Walton (1903-1995), Irish physicist and Nobel Prize winner. Walton advanced the field of nuclear physics significantly, as the first scientist to create a particle accelerator (a device to smash atoms or subatomic particles together at high speeds), the first to split atoms, and the first to transform one element into another. He and British physicist Sir John Douglas Cockcroft won the 1951 Nobel Prize in physics for their atomic research with particle accelerators.
Born in Dungarvan, Ireland, Walton received a B.S. degree in physics and mathematics from Trinity College (the University of Dublin) in 1926, and an M.S. degree in physics from Trinity in 1927. He earned his Ph.D. degree from the University of Cambridge in England in 1930. Walton began his professional career in 1927 at Cambridge's Cavendish Laboratory, as research assistant to British physicist Sir Ernest Rutherford. Walton held this position until 1934, when he accepted a professorship at Trinity College, where he remained until his retirement in 1974.
While working for Rutherford at Cambridge, Walton embarked on research that would bring him wide recognition. He built a linear particle accelerator that was to prove a prototype for subsequent particle accelerators. In 1932, in collaboration with Cockcroft, Walton used this device to bombard lithium atoms, generating enough force to transform each lithium nucleus into two helium nuclei. This marked the first time that human means proved successful in the transmutation of elements (changing one element into another). Walton later succeeded in accelerating protons to such a high velocity that they were able to penetrate atomic nuclei of light elements and start nuclear reactions. He was especially interested in the relations created during this process between the energies of the protons before they hit the nuclei and those of the created nuclear particles. These experiments demonstrated that atomic nuclei contain enormous energies. The research also provided the first experimental confirmation of equations for the equivalence of mass and energy by American physicist Albert Einstein.
Walton's discoveries have had a great influence on the field of nuclear physics in the latter half of the 20th century. Physicists in laboratories in many countries continue to use his methods for accelerating charged particles to produce nuclear reactions.