Nuclear Structure in 146Gd

TL;DR

This study experimentally investigates the nuclear structure of 146Gd, identifying new states and gamma-ray transitions, and conclusively observing a double E3 cascade in two-phonon octupole decay.

Contribution

It provides the first conclusive evidence of a 6+ to 3- to 0+ double E3 cascade in 146Gd, advancing understanding of two-phonon octupole states.

Findings

44 new nuclear states identified

New gamma-ray transitions observed for known levels

First conclusive observation of a double E3 cascade in 146Gd

Abstract

In this work the experimental study of the 144Sm(alpha, 2n) fusion-evaporation reaction is presented. The experiment was carried out at the IKP of the University of Cologne in order to identify double octupole states and two-particle configurations in the 146Gd nucleus. The target was surrounded by a compact array of nine individual Ge detectors and one EUROBALL CLUSTER detector. A total of 44 new states have been identified, as well as new gamma rays corresponding to 26 previously known levels. Among these levels, new candidates for the two-particle configuration states have been found as well as for the (3- x 2+) and (3- x 3-) two phonon multiplets. A very important results of this work is the unequivocal assignment of the 6- member of the two phonon octupole state in 146Gd by identifying the E3 branching to the one phonon 3- state. This result presents the first conclusive observation of a 6+ to 3- to 0+ double E3 cascade in the decay of a two-phonon octupole state.