Low multipolarity magnetic transitions inS32excited by electron scattering

Abstract

Electron scattering cross section measurements on S have been made at incident electron energies between 34 and 74 MeV and at scattering angles of 162. 4' and 180 . Form factors were deduced for transitions to states at 8.11, 9.68, 10.05, 10.78, 11.12, and 11. 63 MeV. Additional peaks at 7.12, 12.02, and 13.36 MeV were observed in some spectra. Comparisons of cross sections at different angles show that the above six transitions are transverse. Comparison of the experimental form factors with those calculated using an oscillator shell model indicate that the 8.11, 9.68, 11.12, and 11. 63 MeV transitions are M1. Transition probabilities 8 (M 1)f = 1.14+0.18, 0.69+0.20, 2.40+0.22, and 1.26+0.20 po, respectively, were determined for these four transitions. The M1 form factors and transition probabilities are also compared with other theoretical shell model calculations. The transition at 10.78 MeV is probably M2, or a mixture of M2 and transverse E2 transitions to unresolved states at about that energy.

l-ForbiddenM1Transition inS32Reitz1, Neumann-Cosel2, Neumeyer3 et al. 1999Phys. Rev. Lett.Self Cite18150View full textAdd to dashboardCite

“…The predictive power of calculations using the USD interaction [21,22] and effective operators is demonstrated by an investigation of the B͑M1͒ strength distribution in 32 S also obtained from the experiments described above. This reaction has been studied previously in electron scattering, but with conflicting results on the strengths of two of the most prominent M1 transitions [27,28]. The upper part of Fig.…”

Recent Progress on Nuclear Magnetic Dipole Excitations

“…The two B(M I) values plotted as dashed bars were obtained in 32S (e, e') experiments(89). The new mode is of a rather pure orbital character since it could not be excited by inelastic proton scattering (9 1, 92) where the spin part of the MI transition operator dominates.…”

Electroexcitation of6−states inS32Clausen1, Lindgren2, Farkhondeh3 et al. 1990Phys. Rev. Lett.Self Cite121110View full textAdd to dashboardCite

“…It is the spectator nucleons in the 2s \n orbit that are responsible for the change in the spectral distribution of T> strength in going from 24 Mg and 28 Si to 32 S. We finally note that a similar change in the distribution of M\ strength between 28 Si and 32 S has been observed. 8 Both the Ml and M6 excitations are built on ^/5/2-hole states, which can be studied by nucleon pickup reactions. These reactions populate 19 only one strong rfs/2-hole state in 24 Mg and 28 Si, but several ds/i states (with about equal strength) in 32 S. The latter observations are also consistent with the shell model.…”