DIS structure functions and the double-spin asymmetry in ${\rho }^0$ electroproduction within a Regge approach

The proton, neutron and deuteron structure functions $F_2{(x,Q}^2)$ and $g_1{(x,Q}^2),$ measured at intermediate $Q^2,$ are analyzed within a Regge approach. This analysis serves to fix the parameters of this scheme which are then used to calculate, in a unified Regge approach, the properties of ${\rho }^0$ meson electroproduction on the proton and the deuteron. In this way, the double-spin asymmetry observed at HERMES in ${\rho }^0$ electroproduction on the proton can be related to the anomalous behavior of the flavor-singlet part of the spin-dependent structure function $g_1{(x,Q}^2)$ at small x.