2006/03/31 by I. Caprini, Irinel Caprini · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1016/j.physletb.2006.06.003
published as Phys.Lett.B638:468-472,2006 · 10 pages, minor text changes, version to appear in Phys.Lett.B
openalex publication_date 2006/06/13 · arxiv created 2006/06/19 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/02
The σ resonance was observed as a conspicuous π+π− peak in hadronic decays like J/ψ→π+π−ω or D+→π+π−π+. The phase of the σ→π+π− amplitude, extracted from production data within the conventional isobar model, is assumed to coincide with that in ππ elastic scattering. We check the validity of this assumption by using Lehmann–Symanzik–Zimmermann (LSZ) reduction and unitarity. The rescattering effects in the final three-particle states are shown to generate a correction to the phase given by a naive application of Watson theorem. We briefly discuss the implications of this result for the pole determination from production data.