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Touschek with AdA in Orsay and the first direct observation of electron-positron collisions

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 نشر من قبل Giulia Pancheri Dr.
 تاريخ النشر 2018
  مجال البحث فيزياء
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We describe how the first direct observation of electron-positron collisions took place in 1963-1964 at the Laboratoire de lAccelerateur Lineaire dOrsay, in France, with the storage ring AdA, which had been proposed and constructed in the Italian National Laboratories of Frascati in 1960, under the guidance of Bruno Touschek. The obstacles and successes of the two and a half years during which the feasibility of electron-positron colliders was proved will be illustrated using archival and forgotten documents, in addition to transcripts from interviews with Carlo Bernardini, Peppino Di Giugno, Mario Fascetti, Francois Lacoste, and Jacques Haissinski.

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In the history of the discovery tools of last century particle physics, central stage is taken by elementary particle accelerators and in particular by colliders. In their start and early development, a major role was played by the Austrian born Brun o Touschek, who proposed and built the first electron positron collider, AdA, in Italy, in 1960. In this note, we present a period of Touscheks life barely explored in the literature, namely the five years he spent at University of Glasgow, first to obtain his doctorate in 1949 and then as a lecturer. We shall highlight his formation as a theoretical physicist, his contacts and correspondence with Werner Heisenberg in Gottingen and Max Born in Edinburgh, as well as his close involvement with colleagues intent on building modern particle accelerators in Glasgow, Malvern, Manchester and Birmingham. We shall discuss how the Fuchs affair, which unraveled in early 1950, may have influenced his decision to leave the UK, and how contacts with the Italian physicist Bruno Ferretti led Touschek to join the Guglielmo Marconi Physics Institute of University of Rome in January 1953.
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