Robert J. Van de Graaff

Robert Jemison Van de Graaff (December 20, 1901 – January 16, 1967) was an American applied physicist and inventor. He is best known for developing the Van de Graaff generator, a high-voltage electrostatic machine that became a fundamental tool in nuclear physics research.

Raised in Tuscaloosa, Alabama, Van de Graaff earned his DPhil degree at Oxford as a Rhodes Scholar. In Europe, exposure to Marie Curie, Ernest Rutherford, and J. Robert Oppenheimer encouraged him to develop methods for accelerating particles to nuclear energies. He built his first electrostatic generator at Princeton University in 1929 and demonstrated a 1.5-million-volt model in 1931, more than twice the highest direct current voltage previously achieved. After joining the Massachusetts Institute of Technology he constructed the 5-megavolt Round Hill generator. He collaborated with John G. Trump, his former student, on creating compact, gas-insulated machines, which became the first accelerators used in clinical medicine. During World War II, he directed development of high-voltage X-ray equipment for the U.S. Navy.