The g factor of the 21+ state in 44Ca has been measured using the transient field technique and Coulomb excitation in inverse kinematics. A positive value of g(21+, 44Ca) = +0.12±0.05 was deduced. The result suggests the (fp)v4 configuration competes with excitations of the 40Ca core. A simple model which considers that the wave function for the 21+ state consists of approximately equal admixtures of spherical four valence neutron configurations and a deformed core configuration accounts for the experimentally observed g factor as well as the previously measured quadrupole moment. © 2003 Published by Elsevier Science B.V.

The systematics of the first 2+ state g factors in the mass 80 region are investigated in terms of an IBM-II analysis, a pairing-corrected geometrical model, and a shell-model approach. Subshell closure effects at N = 38 and overall trends were examined using IBM-II. A large-space shell-model calculation was successful in describing the behavior for N=4 and N=50 nuclei, where single-particle features are prominent. A schematic truncated-space calculation was applied to the lighter isotopes. The variations of the effective boson g factors are discussed in connection with the role of F-spin breaking, and comparisons are made between the mass 80 and mass 180 regions.

The g factors of the 2+1 and 3-1 states in 96Zr have been measured for the first time by Coulomb excitation of 96Zr beams in inverse kinematics using transient magnetic fields. The resulting g factors are g(2+1) = +0.03(7) and g(3-1) = +0.98(15). The lifetime of the 2+1 state, ? = 0.82(10) ps, was redetermined via the Doppler Shift Attenuation Method. The 2+1 ? 0+1 transition rate and the g-factor data are in fair agreement with shell-model calculations involving both proton and neutron excitations. The pronounced octupole strength of the 3-1 ? 0+1 transition is not seen in the g factor which exceeds significantly an expected Z/A value. © 2003 Elsevier Science B.V. All rights reserved.

Greenhouse experiments were carried out to evaluate the effect of different soil-based countermeasures on radiocesium transfer to Medicago sativa (alfalfa) grown on artificially contaminated loamy-clayey soil. Various rates of potassium, ammonium, and Prussian Blue supplements were applied, and the uptake of radiocesium by control and treated alfalfa plants was monitored during four growth periods. Transfer factors ranging between 0.06 and 0.02 were determined for control plants. Application of potassium at rates higher than 0.1 meq per 100 g soil was found to suppress radiocesium uptake, the effect being more pronounced at increasing fertilization rates. On the contrary, soil treatment with ammonium enhanced the bio-accumulation of radiocesium, indicating that Cs+ ions, previously unavailable to plant roots, were released from soil particles. Prussian Blue supplements had practically no effect on soil-to-alfalfa transfer of the radionuclide.

The effects of retardation in the Coulomb excitation of radioactive nuclei in intermediate energy collisions (Elab ? 100 MeV/nucleon) are investigated. We show that the excitation cross sections of low-lying states in 11Be, 38,40,42S, and 44,46Ar projectiles incident on gold and lead targets are modified by as much as 20% due to these effects. The angular distributions of decaying ? rays are also appreciably modified.