1998/03/20 by W. M. Kloet, Wen-Tai Chiang, Frank Tabakin · 1 citation
Physics and Astronomy · #Atomic and Subatomic Physics Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #nucl-th
paper · pdf · doi:10.1103/physrevc.58.1086
published as Phys.Rev.C58:1086-1097,1998 · 22 pages, 3 figures
arxiv created 1998/03/20 · openalex publication_date 1998/08/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
For the photoproduction of vector mesons, all single and double spin observables involving vector-meson two-body decays are defined consistently in the \ensuremathγN center-of-mass frame. These definitions yield a procedure for extracting physically meaningful single and double spin observables that are subject to known rules concerning their angle and energy evolution. As part of this analysis, we show that measuring the two-meson decay of a photoproduced \ensuremathρ or \ensuremathφ does not determine the vector meson's vector polarization, but only its tensor polarization. The vector meson decay into lepton pairs is also insensitive to the vector meson's vector polarization, unless one measures the spin of one of the leptons. Similar results are found for all double spin observables which involve observation of vector-meson decay. To access the vector meson's vector polarization, one therefore needs to either measure the spin of the decay leptons, make an analysis of the background interference effects, or relate the vector meson's vector polarization to other accessible spin observables.