UNSTABLE PARTICLES IN S-MATRIX THEORY

Journal Article · Mon Jul 15 04:00:00 EDT 1963 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.131.888· OSTI ID:4703551

Zwanziger, D

The consequences of the existence of complex poles in scattering amplitudes, corresponding to resonances or unstable particles, are investigated. Specific examples show that corresponding to such poles are normal threshold cuts lying near the physical region and that cause wooly cusps in scattering cross sections. The discontinuity across such a cut is expressed by a unitarity-like relation in terms of unphysical amplitudes with unstable external particles defined by the residues of the complex poles. More generally, it is shown that the Landau equations for the singularities must be extended to include all unstable as well as stable particles. The Cutkosky formulas specify the corresponding discontinuities in terms of the physical and unphysical amplitudes. (auth)

• Research Organization: Univ. of California, Berkeley; Universita, Rome; Istituto Nazionale di Fisica Nucleare, Rome
• NSA Number: NSA-17-028195
• OSTI ID: 4703551
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 131; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

CROSS SECTIONS
DIFFERENTIAL EQUATIONS
ELEMENTARY PARTICLES
FIELD THEORY
MATHEMATICS
MATRICES
PERTURBATION THEORY
PHYSICS
POLOLOGY
RESONANCE
S-MATRIX
SCATTERING
STABILITY