UNITARITY AND ANALYTICITY IN THE COMPLEX ENERGY PLANE OF GENERAL SCATTERING AMPLITUDES
By assuming analyticity in the energy plane and using unitarity, it is found that the relativistic scattering amplitudes of general processes have no singularities in the energy plane except branch points at the thresholds, when keeping the momentum transfer variables in their physical range. These branch points are of the square root type or logarithmic according to whether the number of particles in the corresponding intermediate states is even or odd, respectively. The normal threshold behavior of the Feynman amplitudes is considered in detail and is found to agree with the above results. Continuation of the general amplitudes into their various unphysical Riemann sheets was also obtained. (auth)
- Research Organization:
- Univ. of London
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-18-009145
- OSTI ID:
- 4090516
- Journal Information:
- Nuovo Cimento (Italy) Divided into Nuovo Cimento A and Nuovo Cimento B, Journal Name: Nuovo Cimento (Italy) Divided into Nuovo Cimento A and Nuovo Cimento B Vol. Vol: (10), 30; ISSN NUCIA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
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