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Background: The Cd isotopes are well studied, but experimental data for the rare isotopes are sparse. At energies above the Coulomb barrier, higher states become accessible. Purpose: Remeasure and supplement existing lifetimes and magnetic moments of low-lying states in Cd106. Methods: In an inverse kinematics reaction, a Cd106 beam impinging on a C12 target was used to Coulomb excite the projectiles. The high recoil velocities provide a unique opportunity to measure g factors with the transient-field technique and to determine lifetimes from lineshapes by using the Doppler-shift-attenuation method. Large-scale shell-model calculations were carried out for Cd106. Results: The g factors of the 21+ and 41+ states in Cd106 were measured to be g(21+)=+0.398(22) and g(41+)=+0.23(5). A lineshape analysis yielded lifetimes in disagreement with published values. The new results are τ(Cd106;21+)=7.0(3)ps and τ(Cd106;41+)=2.5(2)ps. The mean life τ(Cd106;22+)=0.28(2)ps was determined from the fully-Doppler-shifted γ line. Mean lives of τ(Cd106;43+)=1.1(1)ps and τ(Cd106;31-)=0.16(1)ps were determined for the first time. Conclusions: The newly measured g(41+) of Cd106 is found to be only 59% of the g(21+). This difference cannot be explained by either shell-model or collective-model calculations.

Following Coulomb excitation of the radioactive ion beam (RIB) 132Te at HRIBF we report the first use of the recoil-in-vacuum (RIV) method to determine the g factor of the 2(+)(1) state: g(973.9 keV 2(+) 132Te) = (+)0.35(5). The advantages offered by the RIV method in the context of RIBs and modern detector arrays are discussed.

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Background: The g factors and lifetimes of the 21+ states in the stable, proton-rich Sn isotopes have been measured, but there is scant information on neutron-rich Sn isotopes. Purpose: Measurement of the g factor and the lifetime of the 21+ state at 1.141 MeV in neutron-rich 126Sn (T 1/2=2. 3×105y). Method: Coulomb excitation in inverse kinematics together with the transient field and the Doppler shift attenuation techniques were applied to a radioactive beam of 126Sn at the Holifield Radioactive Ion Beam Facility. Results: g(21+)=-0.25(21) and τ(21+)=1.5(2) ps were obtained. Conclusions: The data are compared to large-scale shell-model and quasiparticle random-phase calculations. Neutrons in the h 11/2 and d 3/2 orbitals play an important role in the structure of the 21+ state of 126Sn. Challenges, limitations, and implications for such experiments at future rare isotope beam facilities are discussed. © 2012 American Physical Society.

The g factors of 2(1)(+), 4(1)(+), and 2(2)(+) states in the stable Xe-130,Xe-132,Xe-134.136 isotopes have been measured via projectile Coulomb excitation in inverse kinematics in combination with the transient field technique. The results show a steady decrease in g(2(1)(+)) as the number of neutron holes increases in the lighter nuclei below the closed N = 82 neutron shell. The g factors of the 4(1)(+) states in Xe-132,Xe-134 are consistently larger than the g factors of the 2(1)(+) states, a characteristic of proton excitation. The g factors of the 2(1)(+), 4(1)(+), and 2(2)(+) states in Xe-130 are approximately equal as would be expected for vibrational excitations. Physical Review C

The g factors of the 2(1)(+) and 4(1)(+) states in Kr-78,Kr-80,Kr-82,Kr-84,Kr-86 have been measured for the first time, using Coulomb excitation of isotopic Kr beams and the transient field technique. The measured g factors of 2(1)(+) states in Kr-78,Kr-80,Kr-82 are well described, in both magnitude and progression with neutron number, by the IBA-II model. Whereas the lighter isotopes show a dominant collective structure with g factor values close to Z/A, the large g(2(1)(+)) = 1.12(14) value of Kr-86, with its closed N = 50 shell, is unequivocally dominated by specific proton configurations. The g factor of the 2(1)(+) state in Kr-84, with two holes in the 1g(9/2) neutron orbit, reflects both proton and neutron components in the wave function. In addition, the lifetimes of several 2(1)(+) and 4(1)(+) states were remeasured by the Doppler shift attenuation method, yielding values which, in some cases, differ from those in the literature. Physical Review C

The average g factors of high spin, high-excitation energy, quasi continuum structures in 194,193Hg were measured by observing the precessions of the angular distributions of γ-ray transitions in several normal-deformation bands that coalesce in the decay of the entry distribution of states. The average g factors of the states leading to the three main bands in the 193,194Hg isoles were: 〈g(193Hg)〉 = +0.19(1) and 〈g(194Hg)〉 = +0.26(1), respectively. These average g factors are smaller than the average of the g factors of the high energy states in the three superdeformed bands of 194Hg, 〈g(SD;194Hg)〉 = +0.41(8). While the nucleus in the superdeformed well behaves like a rigid rotor, the present results demonstrate the important role played by multiple, quasi particle neutron configurations in the structure of normal-deformation, highly-excited nuclear states.

The average g factors of the high-energy states of the three superdeformed bands in 194Hg were determined directly in a transient field experiment. The reaction 150Nd(48Ca,4n)194Hg at a beam energy of 203 MeV was used to provide recoiling reaction product nuclei with sufficient velocity to traverse a gadolinium ferromagnetic layer. The resulting g factors g(SD1)50.36(10), g(SD2)50.41(20), and g(SD3)50.71(26) are in agreement with cranked Hartree-Fock calculations as well as with the picture of a rigid rotation for which g 5Z/A.