Summary
A review of the events which led to the discovery of the τ-lepton is presented. This work is based on a search of the literature and from the position of responsibility the Author had in the Institute for Nuclear Physics (INFN), responsible for the research activity with the new (e+e−) collider ADONE. The review follows the sequence of events leading to the discovery of the τ-lepton: from the original idea of a Heavy Lepton carrying its own leptonic number, to the invention of the acoplanar (eµ) method and associated technologies (preshower detector), to the evidence that the (eµ) method works, contrary to the prevailing opinion that the high background level could not be controlled. The review is aimed at establishing the sequence of fundamental developments which made this fascinating field possible.
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A proposal to search for Leptonic Quarks and Heavy Leptons produced at ADONE M. Bernardini, D. Bollini, E. Fiorentino, F. Mainardi, T. Massam, L. Monari, F. Palmonari andA. Zichichi:INFN/AE-67/3, 20 March 1967.
Limits on the electromagnetic production of Heavy Leptons V. Alles-Borelli, M. Bernardini, D. Bollini, P. L. Brunini, T. Massam, L. Monari, F. Palmonari andA. Zichichi:Lett. Nuovo Cimento,4, 1156 (1970).
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Validity of the leptonic selection rules for the (μeγ)vertex at high four-momentum transfers V. Alles-Borelli, M. Bernardini, D. Bollini, P. L. Brunini, T. Massam, L. Monari, F. Palmonari andA. Zichichi:Lett. Nuovo Cimento,4, 1151 (1970) and
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How does the muon differ from the electron? M. L. Perl:Phys. Today, July 1971. Here, the source of the new idea for a Heavy Lepton carrying its own leptonic number is correctly quoted,i.e. Zichichi’s work at Frascati [2]. For unknown reasons, Perl calls this Heavy Lepton μ′.
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The discovery of the Tau Lepton M. L. Perl: SLAC-Pub-5937, September 1992 (T/E). Here, the Frascati results are quoted, but no mention of ref. [1].
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Villi, C. The basic steps which led to the discovery of the heavy lepton τ: a historical record. Nuov Cim A 107, 665–673 (1994). https://doi.org/10.1007/BF02732075
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DOI: https://doi.org/10.1007/BF02732075