A ug 1 99 9 Constraints on vector meson photoproduction spin observables
نویسنده
چکیده
Extraction of spin observables from vector meson photoproduction on a nucleon target is described. Starting from density matrix elements in the vector meson’s rest frame, we transform to spin observables in the photon-nucleon c.m. frame. Several constraints on the transformed density matrix and on the spin observables follow from requiring that the angular distribution and the density matrix be positive definite. A set of constraints that are required in order to extract meaningful spin observables from forthcoming data are enunciated. 24.70.+s, 25.20Lj, 13.60Le, 13.88.+e Typeset using REVTEX 1
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تاریخ انتشار 2000