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formed for values of ( Q $^{2}$, W ) corresponding to the first − t bin [2, 4]. The notations for the curves are the same as in Figure 6. In these calculations we used the value of Λ 2 γππ = 0 . 4 GeV $^{2}$. Also here we find a pronounced resonance contribution in dσ$_{T}$/dt , dσ$_{TT}$/dt and dσ$_{LT}$/dt . The slope and magnitude of dσ$_{L}$/dt at forward angles are also affected by the resonances. 

An extraction of l/t partial differential cross sections requires besides the Rosenbluth separation a fit of dif- ferent harmonics in the azimuthal φ -angle distribution of the measured unseparated double differential cross sec- tions. In the actual experiment one measures d $^{2}$σ/dtdφ for two different ε bins. In Figure 8 we show the φ de- pendence of 2 πd $^{2}$σ/dtdφ in the reaction p ( γ ∗ , π $^{+}$) n at fixed − t and two (high and low) values of ε . This is a representative example of φ -dependent exclusive cross sections. In Figure 8 the solid curves are the model re- sults and experimental data are from [1–3]. As in Fig- ures 6 the dashed curves correspond to the contribution 

of the π -exchange and dash-dotted curves do not account for the resonances. The upper set of solid, dashed and dash-dotted curves belongs to the higher value of ε . 

In Figure 9 we confront the result of our calculations with the new JLAB p ( γ ∗ , π $^{+}$) n data [52] for unsepa- rated cross sections dσ$_{U}$/dt , see Eq. (6), at values of W ≃ 2 . 2 ÷ 2 . 4 GeV and for different values of ( Q $^{2}$, ε ) bins. The square symbols connected by solid lines describe the model results. The discontinuities in the curves result from the different values of ( Q $^{2}$, W, ε ) for the various − t bins. The data are very well reproduced by the present model in the measured Q 2 range from Q 2 ≃ 1 GeV 2 up to 5 GeV $^{2}$. In Figure 9 we also show the contribu- tions of the longitudinal εdσ$_{L}$ (dash-dotted curves) and transverse dσ$_{T}$ (dashed curves) cross sections to the to- tal unseparated cross sections (solid curves) for the low- est and highest average values of Q 2 = 1 . 1 GeV 2 and Q 2 = 4 . 7 GeV $^{2}$. The cross sections at high values of Q 2 are flat and totally transverse. At forward angles a strong 

