Summary
It is shown that a production amplitude, considered as a function of a single scalar invariant, inevitably has complex singularities when four other scalar invariants are fixed at physical values. For the processN+π→N+π+π, with the nucleon-nucleon momentum transfer as the variable, the singularities can appear close to the pole to which extrapolations have been made when the other scalar invariants are fixed at typical experimental values.
Riassunto
Si mostra che l’ampiezza di produzione, considerata come funzione di un solo invariante scalare, ha inevitabilmente singolarità complesse quando, entro valori fisici, si fissano quattro altri invarianti scalari. Nel processoN+π→+π+π, prendendo come variabile il trasferimento di impulso nucleone-nucleone, le singolarità possono apparire presso al polo verso il quale si è estrapolato quando agli altri invarianti scalari si assegnano tipici valori sperimentali.
Similar content being viewed by others
References
M. Fowler, P. V. Landshoff andR. W. Lardner:Nuovo Cimento,17, 956 (1960). There is a printing error in this reference: Fig. 1b) should be rotated clockwise through 90°.
For example, the variables used in the heuristic derivation of a dispersion relation byJ. C. Polkinghorne:Nuovo Cimento,4, 216 (1956).
G. F. Chew andF. E. Low:Phys. Rev.,113, 1640 (1959).
R. Ascoli:Nuovo Cimento,18, 754 (1960). See alsoR. Ascoli andA. Minguzzi:Phys. Rev.,118, 1435 (1960).
R. Ascoli:Nuovo Cimento,18, 744 (1960).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Landshoff, P.V., Treiman, S.B. Analytic properties of production amplitudes. Nuovo Cim 19, 1249–1256 (1961). https://doi.org/10.1007/BF02731400
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF02731400