Towards a measurement of the half-life of ⁶⁰Fe for stellar and early Solar System models

Radioisotopes, produced in stars and ejected into the Interstellar Medium, are important for constraining stellar and early Solar System (ESS) models. In particular, the half-life of the radioisotope, ⁶⁰Fe, can have an impact on calculations for the timing for ESS events, the distance to nearby Supernovae, and the brightness of individual, non-steady-state ⁶⁰Fe gamma ray sources in the Galaxy. A half-life measurement has been undertaken at the University of Notre Dame and measurements of the ⁶⁰Fe/⁵⁶Fe concentration of our samples using Accelerator Mass Spectrometry has begun. This result will be coupled with an activity measurement of the isomeric decay in ⁶⁰Co, which is the decay product of ⁶⁰Fe. Preliminary half-life estimates of (2.53 ± 0.24) × 10⁶ years seem to confirm the recent measurement by Rugel et al. (2009).