[en] The (e,e'p) reaction on ⁴He nuclei was studied in kinematics designed to emphasize effects of nuclear short-range correlations. The measured cross sections display a peak in the kinematical regions where two-nucleon processes are expected to dominate. Theoretical models incorporating short-range correlation effects agree reasonably with the data

[en] Two highly segmented plastic-scintillator arrays have been developed for proton detection in electron scattering experiments. The detectors subtend solid angles of 225 and 550 msr and cover energy ranges of 50-225 and 25-165 MeV, respectively. The charge and arrival time of each photomultiplier signal are digitized by flash ADCs and temporarily stored in a dual-port memory. The readout parameters are computer controlled, tuned, and monitored. These detectors have been employed in (e, e'p) and (e, e'pp) experiments for proton emission angles greater than 30 deg. and for luminosities up to 10³⁶ nucleons cm^-2 s^-1. The singles counting rates in the scintillator elements of the first layers were about 0.5x10⁶ particles s^-1 and the trigger rate 1 MHz. The measured resolution in the excitation energy and timing spectra are 2.7% and 0.7 ns, respectively

No abstract available

[en] The double-differential coincidence cross section for the reaction ¹H(e,e'p)π⁰ has been measured at Q²=0.1(GeV/c)² in a range in the invariant mass of 2--14 MeV above threshold. From the angular dependence of the data values of the pion s-wave multipoles E₀₊ and L₀₊ have been extracted. The results are compared to predictions from chiral perturbation theory and models based on an effective Lagrangian. None of the models is able to describe both the E₀₊ and the L₀₊ multipoles

No abstract available

[en] High-momentum components of proton momentum distributions in ²⁰⁸Pb have been studied from 300 to 500 MeV/c with the (e, e' p) reaction. Cross sections were measured with 180 keV excitation-energy resolution for transitions to the low-lying 1/2⁺,3/2⁺,11/2^-,5/2⁺, and 7/2⁺ states in ²⁰⁷Tl. The data are compared to distorted-wave impulse-approximation calculations with mean-field wave functions and with wave functions that include nucleon-nucleon correlations. The data are substantially larger than mean-field predictions. The observed excess strength at low excitation energy appears to be mainly due to long-range correlations and not to short-range and tensor correlations