DOI 10.1007/s100529801002
Energy and Q2 dependence of elastic vectormeson production
and the proton structure function F2
School of Physics and Astronomy, Department of High Energy Physics, Tel-Aviv University, 69978 Tel-Aviv, Israel (e-mail: rueter@post.tau.ac.il)
Received: 27 July 1998 / Published online: 5 October 1998
Abstract
In the framework of the Model of the Stochastic Vacuum elastic
hadron-hadron scattering, photo- and electroproduction of
vectormesons and also F2(Q2) can be well described at center of
mass energy approximately 20 GeV. The scattering amplitude is
derived by smearing the color dipole-dipole scattering, which is
calculated nonperturbatively in the Model of the Stochastic Vacuum,
with appropriate wavefunctions. For the considered processes the
dipoles have extensions in the range of hadron sizes. We now extend
this idea to small dipoles and high energies. The energy dependence
is modeled in a phenomenological way: we assume that there a two
pomerons, the soft- and the hard-pomeron, each being a simple pole
in the complex angular plane. We couple dipoles of hadronic size to
the soft-pomeron and small dipoles to the hard-pomeron. For small
dipoles we take the perturbative gluon exchange into account. By
that way we obtain an energy dependent dipole-dipole scattering
amplitude which can be used for all the processes with the same
parameters. We show that this approach can describe in addition to
all the low energy results (20 GeV) also the HERA data for the
considered processes in a large energy and Q2 range. Especially
the right transition from the soft to the hard behavior is observed.
Copyright Springer-Verlag
