0000000000034422
AUTHOR
E. Monnand
The beta-decay of95Rb and97Rb
Theβ-decay of 377 ms95Rb and 168ms97Rb has been thoroughly investigated by means ofγ-ray, conversion electron andβ-delayed neutron spectroscopy. More than 97% of theβ-decay to particle-bound states has been placed in level schemes of95Sr and97Sr. High-resolution neutron spectroscopic studies have allowed to extend the knowledge of the excitation spectra up to 9 MeV, respectively 10 MeV. The density of neutron-unbound levels in95Sr and97Sr has been derived from peak stripping analyses of the neutron spectra. Beta-strength functions (S β(E)) have been investigated in detail. They indicate that Gamow-Tellerβ-decay of both precursors is dominated by nuclear structure. The discovered pronounced …
Rotational bands in99Sr
The β-decay of 59 ms99Rb has been studied at OSTIS. As is confirmed by RPA calculations with Nilsson model wave functions, the lowest energy levels in99Sr are consistent with rotational bands built on the [411 3/2], [413 5/2] and [422 3/2] Nilsson neutron configurations at 0, 423 and 1071 keV, respectively. All three bands have similar values of the inertial parameter ħ2/2θ indicating a nearly rigid rotor.
Beta-delayed neutrons and high-energy gamma-rays from decay of137I
Beta-delayed neutrons and high-energyγ-rays following decay of137I have been studied in order to characterizeβ-decay to and deexcitation of neutron-unbound levels in137Xe. The totalγ-ray intensity observed accounts for at least 20% of theβ-intensity to levels aboveB n . No evidence was found for neutron andγ-ray emission from the same levels. With the experimentalβ-strength function aboveB n detailed tests were performed on the reproduction of the experimental neutron spectrum, the level density and Porter-Thomas fluctuations of the reducedβ-transition probabilities to highly excited states in137Xe.