Exclusive production of vector mesons ϱ, ϱ′ and ϱ″ by real and virtual photons

✍ Scribed by G. Kulzinger

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 460 KB
• Volume: 74
• Category: Article
• ISSN: 0920-5632
• DOI: 10.1016/s0920-5632(99)00141-3

✦ Synopsis

We present a non-perturbative QCD calculation of high-energy diffractive photo-and leptoproduction of vector mesons p, p' and p" on a nucleon. The initial photon splits up in a qq-dipole and transforms into a vector meson by scattering on the quark-diquark nucleon.

The dipole-dipole scattering amplitude is provided by the non-perturbative model of the stochastic QCD vacuum, the wave functions result from considerations on the light-cone.

We assume the physical p'-and p"-states to be mixed states of an active PS-excitation and a rest whose coupling to the photon is suppressed.

We obtain good agreement with the experimental data and get an understanding of the markedly different spectrum in the K+T--invariant mass for photoproduction and e+e--annihilation.