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[en] The discovery of the 35 cerium isotopes presently known is discussed. Criteria for the discovery of isotopes are suggested and for each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.
[en] Metallic samples of separated Cerium isotopes were prepared by chemical converting Cerium dioxide to the sesquioxide form with a high yield and subsequently reduced in vacuo with Thorium metal powder. The Cerium Metal was obtained in a form suitable for preparing 0.1-2.0 mg/cm2 cyclotron targets
[en] The newly developed multi-quasiparticle triaxial projected shell-model approach is employed to study the high-spin band structures in neutron-deficient even-even Ce and Nd isotopes. It is observed that gamma bands are built on each intrinsic configuration of the triaxial mean-field deformation. Due to the fact that a triaxial configuration is a superposition of several K states, the projection from these states results in several low-lying bands originating from the same intrinsic configuration. This generalizes the well-known concept of the surface gamma oscillation in deformed nuclei based on the ground state to gamma bands built on multi-quasiparticle configurations. This new feature provides an alternative explanation on the observation of two I=10 aligning states in 134Ce and both exhibiting a neutron character.
[en] The angular and energy distributions of α-particles from the reactions 142,144Nd(n,α)139,141Ce have been measured at incident neutron energies of approx. 14.2 and 18.1 MeV. The comparison of the angle-integrated α spectra with those from the reaction 143Nd(n,α)140Ce, shows that the 83th valence neutron of 143Nd acts as a spectator in the (n,α) process, while the two paired neutrons outside the N=82 shell of 144Nd play an active role. This result, together with analogous data from (p,α) reactions, clearly indicates that the protons and the neutrons of the emitted α in a (nucleon, α) reaction must be already paired in the target nucleus
[en] Cerium, an element in the lanthanide series, has a number of radioactive isotopes. Several of these are produced in abundance in nuclear fission reactions associated with nuclear industry operations or detonation of nuclear devices. This report summarizes our present knowledge of the relevant physical, chemical, and biological properties of radiocerium as a basis for establishing radiation protection guidelines
[en] 126-132Ce isotopes, which exhibit enhanced collective behavior and occurrence of first backbend around 10+, are studied in the Variation after Projection (VAP) and Cranked Hartree–Bogoliubov (CHB) frameworks. The pairing plus-quadrupole-quadrupole (PQQ) interaction is employed as an effective interaction. The yrast spectra, B(E2) transition probabilities and variation of moment of inertia versus cranking frequency are studied. Our results show that the backbending arises as a result of the sudden alignment of a pair of protons in the h11/2 subshell. (author)