Virtual Compton scattering measurements in the nucleon resonance region.

We report on new measurements of the electric Generalized Polarizability (GP) of the proton α E in a kinematic region where a puzzling dependence on momentum transfer has been observed, and we have found that α E = (5. 3 ± 0. 6 s t a t ± 1. 3 s y s) 10 - 4 fm3 at Q 2 = 0. 20 (GeV/c)2. The new measurements, when considered along with the rest of the world data, suggest that α E can be described by either a local plateau or by an enhancement in the region Q 2 = 0. 20 (GeV/c)2 to 0.33 (GeV/c)2. The experiment also provides the first measurement of the Coulomb quadrupole amplitude in the N → Δ transition through the exploration of the p (e , e p) γ reaction. The new measurement gives C M R = (- 4. 4 ± 0. 8 s t a t ± 0. 6 s y s) % at Q 2 = 0. 20 (GeV/c)2 and is consistent with the results from the pion electroproduction world data. It has been obtained using a completely different extraction method, and therefore represents a strong validation test of the world data model uncertainties. [ABSTRACT FROM AUTHOR]