IRON 60

Abstract

The long-lived radionuclide Fe⁶⁰ has been observed through extraction of its disintegration product, 10-minute Co^60m, from the iron fraction isolated from a copper target bombarded with ~400-Mev. protons. Direct observation was prevented by the Fe⁵⁹ present. Yield considerations indicate the Fe⁶⁰ half-life to be ~3 × 10⁵ years, uncertain by a factor of 3.