Abstract
The β decay was studied online using mass separation techniques and a first description of the level structure of the neutron-rich isotope with has been obtained. The experiment involved the measurement of β-γ, β-γ-γ, and coincidences as well as neutron spectra by time-of-flight technique. The first low energy level scheme for the daughter nucleus is given with five bound states. Spin and parity assignments are proposed according to β feedings and γ-ray multipolarities. β-strength distribution is evaluated, taking into account - and -emission channels and it is compared with the calculated GT strength distribution. In particular, the and excitations are shown to result in substantial contribution to the low energy configurations. Allowed β branch to the g.s. gives direct evidence for the inversion of and states.
- Received 16 May 2001
DOI:https://doi.org/10.1103/PhysRevC.64.054313
©2001 American Physical Society