Abstract
Precise muonic x-ray transition energies and energy shifts were measured for the -shell nuclei , , , , , , , and . The data were analyzed in terms of the Barrett moments of the nuclear charge distribution, from which equivalent nuclear radii and isotopic and isotonic differences were computed. For those nuclei for which electron-scattering data were available, model-independent rms radii and radius differences were deduced from a combined analysis of the present data and elastic electron-scattering data. The isotope shifts between even- nuclei decrease nearly linearly with increasing and become negative in the second half of the shell; a strong shell-closure effect is evident at . The isotope shifts are independent of , suggesting that the added neutrons interact with the entire proton core rather than with the valence protons. The isotone shifts between even- nuclei decrease smoothly and uniformly with increasing for and are essentially independent of . Like the isotope shifts, the isotone shifts display a sudden increase at . Both the isotope shifts and the isotone shifts show pronounced odd-even staggering. A strong correlation is found between nuclear deformation, as revealed by experimental values, and the measured isotope and isotone shifts. The measured isotope and isotone shifts, including those for odd- nuclei, are satisfactorily described by a simple empirical formula. The experimental results were compared with Hartree-Fock calculations; some recent calculations that include ground-state correlations display improved agreement with experiment through the inclusion of these deformation-related effects.
NUCLEAR STRUCTURE , , , , , , , ; measured muonic x-ray spectra; deduced nuclear charge radii, isotope and isotone shifts; performed model-independent combined analysis of muonic x-ray data and elastic electron scattering data; compared charge parameters with Hartree-Fock and other calculations.
- Received 14 July 1980
DOI:https://doi.org/10.1103/PhysRevC.23.533
©1981 American Physical Society