[en] The status of experiments exploring nuclear structure which have been completed using both pions and electrons is discussed. Inelastic electron scattering to high spin states in the calcium isotopes is underway with preliminary analysis of 150 hours of data completed. The first experimental reparation of the longitudinal and transverse response function in quasi-free scattering has been completed on ⁵⁶Fe with similar work underway for the calcium isotopes. Inclusive electron scattering data from ³He has been analyzed and the application of a new scaling phenomena has provided evidence of high momentum components in the nuclear wave function. Pion-deuteron elastic scattering was completed at LAMPF. An inclusive electron scattering experiment is designed for BATES and development of high pressure gas targets suitable for ³H is underway. A gas cooling system is now available for electron scattering experiments at BATES. A complete series of measurements of pion scattering from ³⁴He has been completed at LAMPF. These include SCE, π-absorption, DCE, elastic and inelastic measurements. Measurements of pion DCE on ¹²C, ⁴⁰⁴⁴⁴⁸Ca, ⁵²Cr, and ⁵⁴Fe have also been accomplished. Pion absorption in ⁶⁷Li and ¹²¹³C was measured at LAMPF. The pickup reaction ¹³C(p,d)¹²C has been investigated at TRIUMF. A minicomputer is on order and expected to be available for data analysis in early 1981. The cryogenic ³⁴He target was modified for experiments at LAMPF

[en] A series of electron scattering experiments is proposed for a quantitative investigation of the structure and dynamics of nuclei. The information developed from the electromagnetic interaction will be used as complement to a series of experiments at LAMPF in which a systematic investigation of the reaction dynamics of pion-nucleus interactions is carried out. Pion induced reactions can supply information on inelastic channels of the nucleon-nucleon interaction which are not as readily available to an electromagnetic probe. Pion absorption experiments designed to measure the off-shell behavior are complemented with a program on pion elastic and inelastic scattering to pursue the on-shell aspect of the π + N interaction. The single (SCE) and double charge exchange (DCE) reactions are unique aspects of π interactions in nuclei. The complementarity of information from different reactions is emphasized in our studies of (e,e'), (p,p'), (π,p) and (p,d) reactions at large momentum transfers (Q greater than or equal to 0.5 GeV/c). Along with the search for the reaction dynamics, the question of new nuclear structure is pursued. We now plan to start a series of experiments that will detect hadrons in the final state along with the scattered electrons. The present success of quantum chromodynamics (QCD) gives increased impetus to pursue experiments that can result in a synthesis of nuclear structure within the framework of the elementary quark; carrying the charge and weak currents within hadrons

[en] Work has continued on the analysis of high momentum transfer data on ³He, ⁴He, and Al from the SLAC experiments. The data collection on ⁴⁸Ca isotope is completed at Bates. A high spin M8 transition has been identified along with some 50 other levels. Analyses of this data is proceeding using microscopic DWBA descriptions of the nucleus The quasi-free scattering from ⁴⁰Ca and ⁴⁸Ca is completed. The preliminary results confirm earlier measurements on ⁵⁶Fe; the Coulomb sum rule is substantially reduced from independent particle models. The study of ⁸⁸Sr and ⁸⁹Y continues with particular emphasis on the extraction of the single particle distribution of the proton and its effect upon nuclear core polarization. Inelastic electron scattering from ¹H, ²H, ³H, ³He and ⁴He has begun at the present Bates linac and measurements at higher energies (750 GeV) are approved for the recirculated beam. Development of high pressure gas targets for Bates and SLAC is continuing and the first versions have mantained beam currents of > 40 μA. The six papers included in the appendix of this report were abstracted and entered in the data base separately

[en] Research in medium and high energy physics consists of the study of electronuclear and pionic reactions with work currently in progress at MIT-Bates, CEN-Saclay, NIKHEF-K, SLAC, and LAMPF. The electron scattering studies consist of nuclear dynamics in the few-body systems /sup 1,2,3/H and /sup 3,4/He, including quasi-free scattering and resonance production; electromagnetic form-factor measurements from ³H on Hg; quasi-elastic measurements from /sup 2,3/H, /sup 3,4/He and /sup 40,48/Ca, ⁵⁶Fe with the attendant assessment of reaction models and nuclear dynamics; nuclear level studies; and nucleon structure and quarks in nuclei. The pion and proton works comprise mainly the determination of reaction mechanisms and the πN and πA hamiltonians and NN interaction potentials. 84 refs., 33 figs

[en] High energy is being conducted at the Stanford Linear Accelerator Center. This includes inclusive electron scattering, electroexcitation of the delta in nuclei, longitudinal and transverse response in the quasi-elastic region, the q² dependence of ⁴He(e,e'p), deep inelastic scattering from nuclei, transverse and longitudinal response in the resonance region, nuclear physics at PEP and 1.6 GeV spectrometer properties. Additional high energy research on electron scattering on ³H and ³He and the nuclear structure of ²⁰⁵Tl and ²⁰⁶Pb are being conducted at MIT-Bates. Other activities are being carried out at Saclay and research and development for Monte Carlo studies of Hall A spectrometers for CEBAF is being conducted

[en] Experiments at the following accelerators were performed and analyzed: the 400-MeV Electron Linac at MIT, the 800-MeV proton accelerator at LAMPF, and the 20-GeV electron Linac at Stanford. Elastic electron scattering from the Pb and He isotopes was carried out to investigate microscopic nuclear structure and the details of the few-body nuclear system. Inelastic electron scattering, with emphasis on quasi-free scattering, was carried out in ⁵⁶Fe and the He isotopes. Elastic and inelastic π⁺ and π^- scattering was done on the Ca isotopes at LAMPF. Double charge exchange reactions, with both (π⁺,π^-) and (π^-,π⁺), were measured on the Ca isotopes. The (π,N) reaction and the single-charge-exchange reaction were measured on ³He and ⁴He. 21 figures

[en] The experimental program has been based upon the selective use of electron and pion probes to investigate fundamental aspects of nuclear structure. The experiments on electron accelerators span the region from low energy (<100 MeV) high resolution work to the region of electron energy where the fundamental description of the nucleus must be changed. The emphasis in the electron experiments is to understand the basic N-N force, in particular the short range behavior of this force and its effect on nuclear properties. The pion reactions have concentrated on the few body system in an attempt to understand the basic pion-nucleon dynamics

[en] Progress is reported on an experiment to study inclusive electron scattering from nuclei. Another experiment is reported that studies electroexcitation of Δ in nuclei. A Cherenkov detector was designed, constructed, and tested for permanent placement in the 1.6 GeV magnetic spectrometer detector system at SLAC. Inclusive electron scattering cross sections have been measured. Deep inelastic scattering of electrons on ²H, ³He, and ⁴He was studied, and the double differential cross-sections spectra obtained are graphed. A proposed experiment to measure electron scattering from tritium and ³He nuclei using a gas target system is described, including a brief description of the target system and of the recent developments in the preparation for the tritium experiment, requirements in the accuracy of the target density, and the performance of the target system used previously. Elastic and inelastic electron scattering from the isotopes ¹⁹⁸Hg and ²⁰⁴Hg are being examined also. 30 refs., 9 figs

No abstract available

No abstract available