No abstract

The inelastic electron-scattering cross sections of H, He, Be, C, and O were measured for 730-MeV electrons scattered at 37.1° for energy transfers to the nucleus up to 550 MeV. The nuclear response in the delta region is found to be quite similar for the A > 1 targets. Although the differential cross section per nucleon at the peak of the delta region (380 MeV) is suppressed compared to that of the free nucleon, the area in the 230-550-MeV region is enhanced for the A > 1 targets.

The reaction n C{e,e'p) in the dip region (o> = 200 MeV, q = 400 MeV/c) has been measured in parallel kinematics for missing energies up to 160 MeV. A coincidence yield considerably larger than that expected for a one-body reaction process is observed, though the one-body contribution from p-and s-shell knockout is also present. A uniform continuum strength extends from beyond the p shell to the highest measured missing energies. This continuum strength is the dominant contribution to the (e,e f p) reaction process in the dip region.PACS numbers: 25.30.Fj

The properties of deep inelastic electron scattering from ' C are analyzed in the context of relativistic y scaling. A large enhancement of the transverse response relative to the longitudinal response is observed in the quasielastic region which is in contradiction to impulse approximation predictions assuming a free one-body current. Scaling behavior is recovered when a relativistic effective mass is included in the nucleon current operator. The first two moments of the longitudinal scaling function are also evaluated.

We measured the 12 C(e,e ′ p) cross section as a function of missing energy in parallel kinematics for (q, ω) = (970 MeV/c, 330 MeV) and (990 MeV/c, 475 MeV). At ω = 475 MeV, at the maximum of the quasielastic peak, there is a large continuum (Em > 50 MeV) cross section extending out to the deepest missing energy measured, amounting to almost 50% of the measured cross section. The ratio of data to DWIA calculation is 0.4 for both the p-and s-shells. At ω = 330 MeV, well below the maximum of the quasielastic peak, the continuum cross section is much smaller and the ratio of data to DWIA calculation is 0.85 for the p-shell and 1.0 for the s-shell. We infer that one or more mechanisms that increase with ω transform some of the single-nucleon-knockout into multinucleon knockout, decreasing the valence knockout cross section and increasing the continuum cross section.