Properties of low-lying intruder states in 34 Al and 34 Si populated in the beta-decay of 34 Mg

Abstract

The results of the IS530 experiment at ISOLDE revealed new information concerning several nuclei close to the N ≈ 20 'Island of Inversion' - 34 Mg, 34 Al, 34 Si. The half-life of 34 Mg was found to be three times larger than the adopted value (63(1) ms instead of 20(10) ms). The beta-gamma spectroscopy of 34 Mg performed for the first time in this experiment, led to the first experimental level scheme for 34 Al, also showing that the full beta strength goes through the predicted 1 + isomer in 34 Al [1] and/or excited states that deexcite to it. The subsequent beta-decay of the 1 + isomer in 34 Al allowed the observation of new gamma lines in 34 Si, (tentatively) associated with low-spin high-energy excited states previously unobserved.