Photoproduction of phi-mesons at threshold using a beam of linearly polarized photons
J. Salamanca 1, P. L. Cole 2*
1 Universidad Distrital Francisco José de Caldas, Bogotá, Colombia
2 Idaho State University
Observables from vector meson photoproduction by linearly-polarized photons can be expressed in terms of bilinear combinations of helicity amplitudes as parameterized by the Spin Density Matrix Elements (SDMEs). These SDMEs, which are reconstructed from the measured polarization observables, give straightforward relations for understanding the nature of the parity exchange at threshold energies, as well as for extracting signatures of the Okubo-Zweig-Iizuka violation. This paper will show our preliminary measurements of the SDMEs for the reaction γp → φp from the g8b experimental data set taken in Hall B of Jefferson Lab. In particular, we shall show the observables from two separate settings covering the respective photon energy ranges: 1.7 to 1.9 GeV (momentum transfer squared t range of −1.2 to −0.25 GeV2) and 1.9 to 2.1 GeV (t range of −1.4 to −0.25 GeV2 ). Significant departure of certain SDMEs from zero will give measure of φ-meson photoproduction arising from mechanisms other than vector meson dominance.