Phenomenology of Vector-Meson Electroproduction on Spinless Targets

Advantages of the amplitude method for the vector-meson-production description in respect of the spin-density-matrix-element (SDME) method are discussed. It is shown that for any nonzero amplitudes the angular distribution of final particles is non-negative. The exact formula for \(R=\frac{d\sigma_{L}}{dt}/\frac{d\sigma_{T}}{dt}\) in terms of the SDMEs for spinless targets and the new approximate formula for nucleons are presented.