[en] Electron scattering from nuclei, with and without coincidence with other outgoing particles, is a tool of remarkable versatility for nuclear structure investigations. Elastic scattering, and inelastic scattering to both discrete and continuum states has led to unique insight into nuclear sizes and shapes, occupancy of single particle orbits, transition charge and current densities, core polarization and correlations, and many other aspects of the structure and dynamics of nuclei. Recent experimental results are reviewed and compared to theoretical models of nuclear structure

[en] Microscopic cross sections measured by thermal neutron activation using RP-0 reactor at the Peruvian Nuclear Energy Institute. The method consists in measuring microscopic cross section ratios through activated samples, requiring being corrected in thermal and epithermal energetic range by Westcott formalism. Furthermore, the comptage ratios measured for each photopeak to its decay fraction should be normalized from interrelation between both processes above, activation microscopic cross sections are obtained

[en] From the decay of their most intense γ-ray spectra the half-lives of ²⁴Na, ³¹Si, ⁴⁹Ca, ⁵²Y, ¹³⁹Ba, ¹⁴²Pr, ¹⁵³Sm, ¹⁵⁹Gd, ¹⁶⁵Dy, ¹⁶⁶Ho, ¹⁷⁵Yb, ¹⁸⁷W, ²³³Th and ²³⁹U were redetermined. The obtained values were found more accurate then the existing ones. (author) 15 refs.; 4 figs.; 2 tabs

[en] Published in summary form only

[en] The compilation of the Japanese Evaluated Nuclear Data Library, Version 3 (JENDL-3) has been made in the Japanese Nuclear Data Committee and is now in a final stage. JENDL-3 has been planned so as to meet requirements from fields of fusion researches and radiation shieldings as well as designs of thermal- and fast reactors. In JENDL-3, much emphasis was placed on improvement of high-energy neutron data, inclusion of photon production data and consideration of measured double differential neutron emission cross sections. Much efforts were also made in full revisions of JENDL-2 data for fissile nuclides and structural materials. This paper gives an outline of JENDL-3 project and the present status of its compilation. (author)

[en] The structure of the vacuum has become of general importance in modern physics. In this context the vacuum of quantum electrodynamics plays a special role because it changes drastically in strong external electric fields and these changes can be followed in a controllable way in the laboratory. It is reviewed how in supercritical electric fields the electron-positron-vacuum, i.e. the ground state of QED is changing from a neutral to a charged vacuum. The theoretical concepts, developed during the last 15 years, can be tested in collisions of very heavy ions, like U-U, U + Cm etc. The important theoretical and experimental stages are described; in particular it is shown that the vacuum decay has recently been experimentally verified: Sharp line structures in the positron spectra with pronounced threshold effects are the signals of this fundamental phase transition. At the same time the positron line structures indicate the existence of rather long-living giant nuclear systems with Z -- 180-190. It is shown that most likely giant nuclear molecules have been formed whose structure can eventually be investigated spectroscopically by the positrons from the vacuum: The positron spectrum should not only show the vacuum decay line, but also Raman and perhaps Stokes-satellites revealing the nuclear collective modes of the giant system formed. Finally the overcritical phenomenon in other areas of physics (e.g. overcritical gluo-electric fields, overcritical gravitational fields) is shortly discussed

[en] The analysis of the neutron spectra from the proton reactions with ²⁷AL , ⁵²Cr, ⁵⁶Fe, sup(58,60)Ni, sup(90,91,94)Zr, ¹¹⁵In and ¹⁸¹Ta are performed. The equilibrium emission neutron spectra are described on the basis of the statistical theory, the level density parameters of 30 nuclei are determined. A comparison is made with the results of a similar analy ysis of experimental data from the (p, xn) reaction at Esub(p)=11 MeV. Cross sections of some evaporation steps are compared with the experiment. Most of th he nuclei investigated exhibit a certain decrease in the energy-level density as compared with the data obtained at Esub(p)=11 MeV, the tungsten isotopes pre esenting an exseption. The w isotopes have energy-level densities by about 10% higher than the data at Esub(p)=11 MeV. The computation results point to a significant role of the radiation channel at the decay last stage

[en] Earlier unknown total cross sections and cross sections of inelastic interactions of antiprotons with C, Al, Ti, Cd nuclei at the incident antiproton momenta of 1.45 and 1.8 GeV/c are measured. Measurements are carrned out by the transmission method using the secondary universal beam of the ITEP proton synchrotron. Multiwire proportional chambers were used instead of traditional scintillation counters. The measurement method is described and the results are presented. The proton interaction cross sections with these nuclei at the momenta of 1.52 and 1.8 GeV/c are also presented. A part of the data on the proton interactions are used to test the measurement method, and some data are new. Coincidence of measurement results with data of other papers confirms the method measurements. The results are described reasonably by means of the Glauber multiple scattering theory

[en] The preequilibrium, statistical nuclear code GNASH developed at LANL provides a useful device to evaluate secondary gamma-ray and particle emission cross sections. The new version (2/17/84 version) has been converted into FORTRAN-77 language in FACOM-M380 and ACOS-1000. It was improved in LANL by adopting master equation model for preequilibrium process and adding new input formats for level density parameters and gamma-ray strength functions. Additionally, we improved it by adopting the recent works for nuclear level density by Gruppelaar et al. and Yamamuro. The code runs after the spherical optical model calculation by ELIESE-3 to obtain the particle transmission coefficients. It is found that the calculated results for sample problem are sensitive to nuclear level density parameters of daughter nuclei. In the paper, future scope of the code is also described. (author)

[en] Results of recent measurements on isotope shifts are compiled for 20 chains of isotopes, mostly concerning short-lived radioactives. Unpublished material is also included. The delta< r²> are re-evaluated by using an improved calculation of the electron density at the nucleus. Therefore, in some elements, minor changes occur as compared to results given in the literature. (Auth.)