Emilio Segrè (b. Tivoli, Italy, 30 January 1905; d. Lafayette, California, 22 April 1989) was an Italian physicist and Nobel Prize laureate. He discovered the elements technetium and astatine, and the antiproton, a sub-atomic antiparticle.
According to Encyclopedia.com:
Segrè opened the world of antimatter to physical investigation with his discovery of the antiproton, discovered the first of the elements produced by a particle accelerator, provided the critical measurements that established the need for implosion in the ignition of nuclear weapons, and provided important resources for the historical understanding of modern physics.
He first studied engineering before taking up physics. He was the professor of physics at the University of Rome from 1932 to 1936.
His autobiography, A Mind Always in Motion, was published in 1993.