0000000000449152
AUTHOR
Gérard Lhersonneau
First decay study of the very neutron-rich isotope 93Br
The decay of the mass-separated, very neutron-rich isotope 93 Br has been studied by γ spectroscopy. A level scheme of its daughter 93 Kr has been constructed. Level energies, γ-ray branching ratios, and multipolarities suggest spins and parities which are in accord with a smooth systematics of the N = 57 isotones for Z <~ 4 0 , suggesting the N = 56 subshell closure still to be effective in Kr isotopes. So far, there is no indication of a progressive onset of deformation in neutron-rich Kr isotopes. peerReviewed
βdecay of neutron-rich118Agand120Agisotopes
$\ensuremath{\beta}$ decays of on-line mass-separated neutron-rich ${}^{118}\mathrm{Ag}$ and ${}^{120}\mathrm{Ag}$ isotopes have been studied by using $\ensuremath{\beta}\ensuremath{-}\ensuremath{\gamma}$ and $\ensuremath{\gamma}\ensuremath{-}\ensuremath{\gamma}$ coincidence spectroscopy. Extended decay schemes to the ${}^{118,120}\mathrm{Cd}$ daughter nuclei have been constructed. The three-phonon quintuplet in ${}^{118}\mathrm{Cd}$ is completed by including a new level at 2023.0 keV, which is tentatively assigned the spin and parity of ${2}_{4}^{+}.$ The intruder band in ${}^{118}\mathrm{Cd}$ is proposed up to the ${4}^{+}$ level at 2322.4 keV. The measured $\ensuremath{\beta}$-decay half…
Identical transitions in the strongly deformed 99Sr and 100Sr
The decay of the very neutron-rich nucleus 100 Rb has been studied by γ spectroscopy of online mass-separated samples. Schemes for β decay to 100 Sr and β n decay to 99 Sr are presented. New sets of transitions in 99 Sr and 100 Sr with identical energies are observed. All identical bands so far observed in neutron-rich Sr isotopes obey a simple energy rule valid for even-even, odd-even, and odd-odd bands. peerReviewed
Beta decay of neutron-rich 118Ag and 120Ag isotopes
b decays of on-line mass-separated neutron-rich 118Ag and 120Ag isotopes have been studied by using b-g and g-g coincidence spectroscopy. Extended decay schemes to the 118,120Cd daughter nuclei have been constructed. The three-phonon quintuplet in 118Cd is completed by including a new level at 2023.0 keV, which is tentatively assigned the spin and parity of 24 1 . The intruder band in 118Cd is proposed up to the 41 level at 2322.4 keV. The measured b-decay half-life for the high-spin isomer of 120Ag is 0.4060.03 s. Candidates for the three-phonon states, as well as the lowest members of the intruder band in 120Cd, are also presented. These data support the coexistence of quadrupole anharmon…
b-decay of 116Agm and the vibrational structure of 116Cd
The structure of near neutron midshell 116 Cd has been investigated via β decay of 116 Ag m by β-γ and γ-γ coincidence spectroscopy. The 116 Ag m activity was produced by symmetric fission of natural uranium induced by 25 MeV protons. The ion guide technique has been employed to produce online mass separated sources. The decay scheme of 116 Ag m has been considerably extended by adding 19 new excited states of 116 Cd . The newly identified 116 Cd state at 1869.7 keV, along with other four levels near 2 MeV, are interpreted as forming the complete three-phonon quintuplet. The vibrational structure of 116 Cd is discussed in the context of an anharmonic vibrator. peerReviewed