Comparison of the ^<40>Ca (e, e\u27p) Cross Section at Low Momentum Transfer Region with Relativistic Calculations(I. Nuclear Physics)

Both theoretical calculations using the spectroscopic factor obtained in the parallel and constant (ω, q) kinematics. overestimate the experimental cross section, about factors 2 or 1.4, respectively. The (e, e\u27p) experiment at the low momentum transfer in ^C, ^O and ^Ca show some important contributions is missing in the theoretical approach. The authors would like to thank C. Giusti and A. Meucci for their relativistic calculations. They also thank the accelerator group, the computer group and Mr. Matsuda for their assistance to the experiment. This work has been supported by Grant-in-Aid for Scientific Research (KAKENHI) (No.14540239, No.17540229) from Japan Society for the Promotion of Science (JSPS)

Double Pion Photoproduction on Deuteron(I. Nuclear Physics)

Exclusive cross sections for double-pion photoproductions on proton and deuteron were measured in an energy range from 0.8 to 1.1GeV using tagged photons at Laboratory of Nuclear Science, Tohoku University. We employed the Neutral Kaon Spectrometer (NKS) to detect two pions in the final state, and deduced the cross section for the π^+π^- photoproduction on the "free" and "bound" proton. We have discriminated between the quasi-free and non-quasi-free process applying the kinematical cut on the missing momentum. We found that the total cross section for the γ"p"→pπ^+π^- reaction was about 60% of that for the "free" proton, and this is consistent with the previously obtained data. The one of the dominant part of the non-quasi-free process was found to be the double Δ production. Its cross section is smaller than the previous investigations