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Electron form factors up to fourth order. - I

Электронные форм-факторы с точностью вплоть до четвертого порядка. I

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Il Nuovo Cimento A (1965-1970)

Summary

The explicit results of the analytic evaluation of the discontinuities of the electron form factors and of their zero-momentum-transfer values, up to the fourth order of the perturbative expansion of QED in the electric charge, are presented. Asymptotic and threshold behaviours are discussed. The related form of the dispersion relations for the real parts is given.

Riassunto

Si presentano i risultati espliciti del calcolo analitico delle discontinuità dei fattori di forma dell’elettrone e dei loro valori a momento trasferito nullo, sino al quart’ordine dello sviluppo perturbativo dell’elettrodinamica quantica nella carica elettrica. Si discutono i comportamenti asintotici e in soglia. Si dà la corrispondente forma delle relazioni di dispersione per le parti reali.

Реэюме

Предлагаются точные реэультаты аналитического вычисления раэрывов злектронных форм-факторов и их эначений при нулевых передаваемых импульсах с точностью вплоть до четвертого порядка теории воэмушений по злектрическому эаряду в квантовой злектродинамике. Обсуждаются асимптотическое и пороговое поведения. Приводится соответствуюшая форма дисперсионного соотнощения для вешественных частей.

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Authors and Affiliations

  1. Scuola Normale Superiore, Pisa

    R. Barbieri

  2. Departamento de Física, Facultad de Ciencias Exactas y Ingenieria, Universitad Nacional de Rosario, Rosario

    J. A. Mignaco (Member)

  3. Carrera del Investigator Cientifico, Universitad Nacional de Rosario, Rosario

    J. A. Mignaco (Member)

  4. Istituto di Fisica dell’Università, Bologna

    E. Remiddi

  5. Istituto Nazionale di Fisica Nucleare, Sezione di Bologna

    E. Remiddi

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  1. R. Barbieri
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  3. E. Remiddi
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Barbieri, R., Mignaco, J.A. & Remiddi, E. Electron form factors up to fourth order. - I. Nuov Cim A 11, 824–864 (1972). https://doi.org/10.1007/BF02728545

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