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The multipole decomposition analysis (MDA) for the inelastic alpha scattering is very useful to determine the strength distribution, and widely used to study the cluster structures in nuclei. However, the reliability of the MDA was shaken by the puzzle of the missing monopole strength in 12C, where the monopole strength for the Hoyle state determined by the inelastic alpha scattering is much smaller than by the inelastic electron scattering. In the present work, we systematically measured cross sections of the inelastic alpha scattering at Eα=130 and 386 MeV exciting low-lying discrete states in 12C, 16O, 20Ne, 24Mg, 28Si, and 40Ca. In addition, we compared the measured cross sections with the “parameter-free” distorted-wave Born-approximation (DWBA) calculation. All of the adjustable parameters in the DWBA calculation were determined by the electromagnetic transition strengths and the elastic alpha scattering.We found that this puzzle is not specific to the Hoyle state in 12C but universally observed in all of the ΔL = 0 transitions, and the DWBA calculation with the density-independent effective αN interaction at Eα = 386 MeV is better than that with the density-dependent effective αN interaction. The inadequate density dependence in the effective αN interaction causes this puzzle by overestimating the cross sections for the ΔL = 0 transition. However, it is still unsatisfactory to reproduce the experiment. The present data will provide valuable information to develop a new sophisticated interaction which includes the proper density depend.

It is demonstrated that the JLab proton polarization data puzzle could be solved by the new sum rule giving into a relation proton and neutron Dirac and Pauli form factors in the space‐like region with a difference of the differential proton and neutron cross sections describing just Q2 distribution in deep inelastic electron scattering process.

Recent results in the 3N and 4N systems are reviewed, including inelastic electron scattering.

We report new results on a precision measurement of the ratio R=σL/σT from deuterium, iron and gold targets, on the ratio σFe/σD and on the structure function F2, for deep inelastic electron‐nucleus scattering in the range 0.2≤x≤0.5 and 1≤Q2≤10(GeV/c)2. We find no difference between RFe and Rd. Our results show, for first time, a clear falloff of R with increasing Q2 at SLAC energies. Our R and F2 results are in good agreement with QCD predictions only when corrections for target mass effects are included.

Some examples of developments in the field of inelastic electron scattering are given including the physics of this study, an application of electromagnetic transition densities to beta decay, negative muon capture, and positive pion photoproduction in lithium-6 and helium-6, giant resonances, vibrational states in zinc-64, -66, and -68, shapes of deformed nuclei, recent results from Saclay on chromium-52, and recent results from MIT. (JFP)

Cross sections for 180° inelastic electron scattering from the deuteron were measured from the break‐up threshold to beyond the quasielastic peak for incident beam energies between 0.7 and 1.3 GeV, corresponding to 0.75≤Q2≤2.75 (GeV/c)2. The data are in reasonable agreement with nonrelativistic models that include final‐state interactions are meson exchange currents.