Background-free beta-decay half-life measurements by in-trap decay and high-resolution MR-ToF mass analysis

A method paper showing how to measure β-decay half-lives without the usual radioactive background, by letting the parent decay inside the trap and identifying the daughter by mass.

Parent ions are stored so the decay happens in trap. The daughter is then counted with high-resolution MR-ToF mass analysis, which separates it from leftover parents and contaminants.

Conventional half-life counts drown in room background and isobaric activity. In-trap decay plus MR-ToF turns the mass peak itself into the clock, which later ISOLTRAP work near N=20 reused.