Implosion Nuclear Weapons with 60%-Enriched Uranium

This work considers the direct use of 60%-enriched uranium in pure fission nuclear weapons. From numerical simulations and simple analytics this work shows that substituting a weapons-grade core for a 60%-enriched core reduces the yield by a factor of 4 to 5 that is fairly insensitive to classified design details. A weapon designed to achieve a nominal 10 kt yield using weapons-grade uranium could therefore still produce a modest yield of 2-3 kt using a core of lower enrichment.