14 research outputs found
Contribution of quasiparticle-phonon, recoil and coriolis interactions in describing low-lying states of isotope
A quasiparticle-phonon coupling based on one quadrupole phonon is developed.
The coupling is constructed by using a deformed average field of Nilsson, a
monopole pairing interaction and a quadrupole-quadrupole force. Microscopic
structure of the quadrupole phonon is given from the Tamm-Dancoff
Approximation. The two effects of recoil and Coriolis forces are included
with the assumption of a symmetric rotational motion. Since theoretical
treatment is performed for an odd- nuclei the configuration of intrinsic
states should contain both one-quasiparticle and quasiparticle-phonon
components. This method is applied to describe the level scheme of
for which an agreement with experimental data is obtained. The results are
also found similar to previous calculations obtained by the Particle plus
Triaxial Rotor Model
The \chem{^{130}Nd\to{}^{130}Pr\to{}^{130}Ce} decay chain revisited
An investigation of low-lying energy levels of Pr
and Ce has been made via -decay. The radioactive parent
nuclei were produced via Mo + Ca reactions at 6.8
MeV/nucleon and transported by a He-jet system. Gamma--t,
-X-t, -e-t coincidence measurements were
performed. Internal conversion coefficients have been measured with a
magnetic spectrometer. The new -decay half-life of Nd
has been determined to be 21(3) s. A partial level scheme of
Pr at low-spin has been constructed. The -decay of
Pr to Ce suggests the existence of three
-instable isomeric states in Pr, while only one
half-life s has been measured. Based on the present
work and low-lying excited states in neighbouring odd-mass nuclei, the
spins and parities of isomeric states in Pr are proposed to be
2, (4,5) and (7,8). The ground state in Pr is
still undetermined
Level structures of Ce observed in beta decay
The low-lying levels of the odd-mass nuclei 131 Ce and 129 Ce have been investigated by means of the β + EC decays of 131g+m Pr and 129 Pr, respectively, The Pr nuclei were obtained by bombarding 94,96 Mo targets with a 255 MeV 40 Ca beam. The radioactivities produced in the reactions were transported with a He-jet device and γγt , X γt , e − γt coincidence measurements were performed. Conversion electrons were measured with a magnetic spectrometer and transition multipolarities were deduced. On-line mass separation was used to select the 129 Pr β-decay. The resulting level schemes of 131,129,127 Ce are discussed in connection with level systematics and calculations performed by using the Interacting Boson-Fermion Model (IBFM). (Elsevier