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γ $^{µ}$γ$_{5}$ vertex is C -parity even and can not couple to the b 0 $_{1}$(1235)-meson which has negative C -parity. This is op- posed to the a$_{1}$ (1260) which couples to γ $^{µ}$γ$_{5}$ . By C ( G )- parity only a tensor b$_{1}$NN coupling, Eq. (40), is possible. We have checked and found that with the proper b$_{1}$NN vertex this extraction is not obvious. With the tensor in- teraction the exchange of the b$_{1}$ (1235) trajectory is neg- ligibly small and can be readily neglected. For instance, using G$_{b}$$_{1}$$_{NN}$ = G$_{a}$$_{1}$$_{NN}$ or even increasing considerably the latter value does not produce any noticeable effects on the observables considered here. 

## VI. ELECTROPRODUCTION ABOVE THE RESONANCE REGION 

In this section we demonstrate the resonance interpre- tation proposed in this work and fix the model parame- ters using the JLAB data. At first, we briefly consider the real photon limit of the Regge amplitudes at high energies. In π + and π − photoproduction at very forward angles the reggeized electric amplitudes, see Eqs. (9) and (10), are supposed to be dominant. Since the vector and axial-vector meson-exchange contributions vanish at for- ward angles, Eqs. (9) and (10) are parameter free, pro- vided the intercept of the π -trajectory and the g$_{πNN}$ cou- pling constant are fixed. However, further assumptions concerning a choice of the phases in the Regge amplitudes 

have to be made. In the gauged π -Regge amplitudes, Eqs. (9) and (10), an assumption concerning an exact degeneracy of π and axial-vector b$_{1}$ (1235) Regge trajec- tories with a choice of rotating phase in π + and a constant phase in π − photoproduction yields a remarkable consis- tency with data [29]. The degeneracy of ρ (770) /a$_{2}$ (1320) Regge trajectories and G -parity arguments result in a ro- tating phase in π + and a constant phase in π − production described by the ρ -exchange amplitude, Eq. (33). Here, to be consistent with the real photon limit, we follow these assumptions [29]. However, in the high- Q 2 elec- troproduction a particular choice of phases in the Regge amplitudes is of minor importance. The virtual photon ( γ ∗ , π ± ) results presented here can be well reproduced with the standard Regge propagators. From the meson spectrum there is no conclusive evidence that a leading Regge trajectory for an unnatural parity ρ$_{2}$ state exists. Therefore, we do not make any assumptions on a degen- eracy pattern of a$_{1}$ (1260). 

The resulting Regge model based on reggeized gauge invariant Feynman amplitudes describes the high energy π ± photoproduction data relevant for the present studies reasonably well. These include the differential cross sec- tions above the resonance region, the π − /π + ratio of the n ( γ, π − ) p and p ( γ, π $^{+}$) n differential cross sections and polarized photon asymmetries. Our description of pho- toproduction data is quantitatively similar to the results of Ref. [29] and we do not repeat this comparison with 

