A. Airapetian et al., Exclusive leptoproduction of p(0) mesons from hydrogen at intermediate virtual photon energies, EUR PHY J C, 17(3), 2000, pp. 389-398
Measurements of the cross section for exclusive virtual-photoproduction of
rho (0) mesons from hydrogen are reported. The data were collected by the H
ERMES experiment using 27.5 GeV positrons incident on a hydrogen gas target
in the HERA storage ring. The invariant mass W of the photon-nucleon syste
m ranges from 4.0 to 6.0 GeV, while the negative squared four-momentum Q(2)
Of the virtual photon varies from 0.7 to 5.0 GeV2. The present data togeth
er with roost of the previous data in the intermediate W-domain are well de
scribed by a model that infers the W-dependence of the cross section from t
he dependence on the Bjorken scaling variables of the unpolarized structure
function for deep-inelastic scattering. In addition, a model calculation b
ased on OR-Forward Parton Distributions gives a fairly good account of the
longitudinal component of the rho (0) production cross section for Q(2) > 2
GeV2.