Bruno Touschek: Particle Physicist and Father of the e^+e^- Collider

This article gives a brief outline of the life and works of the Austrian physicist Bruno Touschek, who conceived, proposed and brought to completion the construction of AdA, the first electron-positron storage ring. The events which led to the approval of the AdA project and the Franco-Italian collaboration which confirmed the feasibility of electron-positron storage rings will be recalled. We shall illustrate Bruno Touschek's formation both as a theoretical physicist and as an expert in particle accelerators during the period between the time he had to leave the Vienna Staat Gymnasium in 1938, because of his Jewish origin from the maternal side, until he arrived in Italy in the early 1950s and, in 1960, proposed to build AdA, in Frascati. The events which led to T's collaboration with Rolf Widero e in the construction of the first European betatron will be described. The article will make use of a number of unpublished as well as previously unknown documents, which include an early correspondence with Arnold Sommerfeld and BT 's letters to his family in Vienna from Italy, Germany and Great Britain. The impact of Ts work on students and collaborators from University of Rome will be illustrated through his work on QED infrared radiative corrections to high energy e^+e^- experiments and the book Meccanica Statistica.