Whose discovery first identified technetium as the first element produced artificially?

Emilio Segrè and Carlo Perrier identified technetium in 1937 from a sample that had been irradiated in a cyclotron. Technetium was the first element to be created artificially rather than found naturally on Earth in measurable amounts. Its discovery filled a long-standing gap in the periodic table and proved that human-made nuclear reactions could produce new elements. Technetium later became important in nuclear medicine, especially in medical imaging. It is also notable as the lightest element with no stable isotopes.