Mass measurements of neutron-rich isotopes near N=20 by in-trap decay with the ISOLTRAP spectrometer

Masses of neutron-rich nuclei near the N=20 island of inversion, obtained by creating the ion of interest through decay inside the ISOLTRAP spectrometer.

A longer-lived parent is trapped and decays in situ. The daughter mass is then measured, which is how species that ISOLDE cannot deliver as a clean beam still become accessible.

N=20 is where ³²Mg and neighbours stop behaving like a closed shell. Masses there are the ground-state test of that inversion, and in-trap decay is what reaches the hardest cases.