D.L. Hendrie

Determination of Y40 and Y60 components in the shapes of rare earth nuclei

Abstract Differential cross sections for 50 MeV alpha particles of members of the ground state rotational band up to the 6 + or 8 + state were measured in a number of even nuclei of the rare earth region. The data were analyzed under the assumption of a perfect rotor description for the nucleus and a deformed optical interaction between alpha and nucleus by solving the resulting coupled equations. Higher order components Y 4 and Y 6 in the nuclear shapes were determined with precision. A systematic variation of B 4 from positive values in the light rare earths to negative values in the heavy ones is established.

RELATION BETWEEN THE OPTICAL POTENTIAL FOR SPHERICAL AND DEFORMED NUCLEI.

Abstract It is shown that when the contribution of the strong collective states to the optical potential is removed by treating them explicitly through solution of the coupled equations describing the scattering, the resulting optical potential is valid for both spherical and deformed nuclei over a broad mass range in the rare earth region. In a search for the nuclear shape in the deformed region, this has the very important effect of removing the optical parameters from the list of free parameters.

INFLUENCE OF INTRINSIC NUCLEON MOTION ON ENERGY SPECTRA AND ANGULAR DISTRIBUTIONS FOR 16O-INDUCED REACTIONS AT 20 MEV/A

Abstract Energy spectra and angular distributions for peripheral reactions induced by 16 O on 208 Pb at 20 MeV/ A can be explained in terms of the intrinsic nucleon motion of the excited projectile, in a manner similar to the interpretation of projectile fragmentation reactions at 2.1 GeV/ A .

The (d, 6Li) reaction on light nuclei

Abstract The (d, 6 Li) reactions on 12 C, 16 O, 20 Ne, 24 Mg and 25 Mg have been studied at 55 MeV incident energy. Some features of the data appear consistent with an α-particle pickup model of the reaction. The 24 Mg (d, 7 Li) 20 Ne results complement previously published 16 O( 7 Li, t) 20 Ne work and support the Elliot SU 3 classification scheme for low-energy states of 20 Ne.

High energy proton emission in reactions induced by 315 MeV 16O ions

Abstract Inclusive proton spectra have been measured for the reaction 197Au(16O, p)X at 315 MeV. The data, which are consistent with emission from a moving source, are compared with the fireball model and with models preequilibrium emission.

Comparison of the elastic scattering of 3He and 4He by 40Ca

Abstract The scattering of 3He and 4He from 40Ca has been compared at equal incident momenta. The results indicate that 3He has a more diffuse interaction than 4He.

Multiple nuclear excitation of rotational levels in 152Sm and 154Sm

Abstract By observing the inelastic scattering of 50 MeV alpha particles from samarium, we have made a definite correlation between reversed phase angular distributions and double excitation of second excited rotational levels. For the first time, we have also seen triple excitation of third excited rotational levels.

Fragmentation of the octupole strength in 205Tl(p,p′)205Tl

Abstract In addition to the octupole transitions to the apparent weak-coupling doublet [3 s 1 2 −1 , 206 Pb 3 − ] at 2.62–2.71 MeV, three other strong octupole transitions to nearby states are observed in the inelastic scattering of 20 MeV protons from 205 Tl. Two of these extra states, at 3.21 and 3.26 MeV, may arise from the [2 d 3 2 −1 , 206 Pb 3 − ] configuration. It is not likely that the other transition (2.48 MeV) can be described by the simple weak-coupling model.

Single-particle proton admixtures in core-excited states of 207Bi☆

Abstract At least 18 states up to 3.5 MeV of excitation have been observed in the 206Pb(3He, d)207Bi reaction at 35 MeV. The experimental spectrum and spectroscopic factors are in fair agreement with the predictions of the weak-coupling model up to an excitation energy of 2.5 MeV.

Trends of isotope yields observed in reactions induced by 16O ions of 140, 315 and 33600 MeV

Abstract Isotope yields from reactions induced by 16 O ions of 140 and 315 MeV on 94 Zr, 197 Au, 208 Pb and 232 Th targets are measured and compared with published data at 33.6 GeV. The previously reported similarity of cross sections at 315 MeV and 33.6 GeV is augmented by the fact that the relative isotope yields are essentially target independent at 315 MeV (as has been established at 33.6 GeV). Significant differences are observed between cross sections at 140 and 315 MeV.