Nuclear g-factor measurements for the 2$_{1}^{+}$ states of radioactive Te isotopes by the recoil-in-vacuum technique

Coulomb excitation of the first excited state of radioactive ion beams has been carried out at HRIBF by scattering the RIBs from C foils and observing the recoiling C ions and de-excitation gamma rays of the RIB.\footnote{See e.g., D. C. Radford, et al., Phys. Rev. Lett. 88, 222501 (2002).\par } This method also yields an angular correlation of the emitted gamma ray with respect to the direction of C recoil. In Coulomb excitation the nuclear spin is initially oriented by the reaction, yielding strong angular correlation of the emitted gamma ray with respect to the direction of C recoil. As the RIB recoils into the vacuum downstream from the thin target, the angular correlation is attenuated due to de-orientation of the spin resulting from its precession about the total angular momentum of the ion. The attenuation of the angular correlation depends on g$^{2}$ and the mean life of the state. The experimental results for $^{132}$Te will be presented and the g-factors of $^{132,134,136}$Te will be discussed.