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Constraints on vector meson photoproduction spin observables

W. M. Kloet·Frank Tabakin
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Abstract

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.

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W. M. Kloet, Frank Tabakin. 1999-08-20. Constraints on vector meson photoproduction spin observables. https://doi.org/10.1103/physrevc.61.015501

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