Shape transitions far from stability: The nucleus 58Cr

Abstract Excited states up to I π = 8 + in the neutron-rich nucleus 58Cr have been identified by using a new experimental setup composed of the large acceptance magnetic spectrometer PRISMA and the highly efficient γ-detector array CLARA. Interestingly, the excitation energy sequence of the ground-state band follows the one expected by the E ( 5 ) dynamical symmetry for a nucleus at the critical point of the shape phase transition from a spherical vibrator ( U ( 5 ) ) to a γ-soft rotor ( O ( 6 ) ). For the first time, in the same physical system, large scale shell-model calculations in the full fp shell are compared to the E ( 5 ) analytical model results and to the Interacting Boson Model. The theoretical results are in excellent agreement with the present data

High-spin level structure of 35 S

The nucleus 35S has been studied by in-beam ?-ray spectroscopy using the 24Mg(14N,3p) fusion-evaporation reaction at Elab=40 MeV. A level scheme extended up to J?=17/2+ at 8023 keV and J?=13/2- at 6352 keV has been established. Lifetimes of six excited states have been determined by applying the Doppler shift attenuation method. The experimental data have been compared with the results of large-scale shell model calculations performed using different effective interactions and model spaces allowing particle-hole excitations across the N=Z=20 shell gap. © 2014 American Physical Society

Spectroscopy of the deformed \chem{^{126}Ce} nucleus

The even-even nucleus \chem{^{126}Ce} was studied via in-beam $\gamma$-ray spectroscopy using the \chem{{^{40}Ca}+{^{92}Mo}} reaction at 190 MeV. Five bands were observed, one of them being identified for the first time. New connecting transitions were identified between the bands, which lead to new spin assignments. The bands are discussed in the framework of the IBM + broken pairs model

Spectroscopy of the deformed \chem{^{125}Ce} nucleus

The odd-even nucleus $^{125}$Ce was studied via in-beam $\gamma$-ray spectroscopy using the \chem{^{40}Ca+{}^{92}Mo} reaction at 190 MeV. Four rotational bands were observed, two of them being identified for the first time. New connecting transitions were identified between the bands, which leads to new spin assignment for one of the previously known bands. We propose $J=7/2^-$ for the ground state of $^{125}$Ce. The bands are discussed in the framework of the \chem{IBFM+broken}-pairs model