2022MNRAS.509.3163P

Core-collapse supernovae (CCSNe) produce large (≳0.1 M_☉) masses of dust, and are potentially the primary source of dust in the Universe, but much of this dust may be destroyed before reaching the interstellar medium. Cassiopeia A (Cas A) is the only supernova remnant where an observational measurement of the dust destruction efficiency in the reverse shock is possible at present. We determine the pre- and post-shock dust masses in Cas A using a substantially improved dust emission model. In our preferred models, the unshocked ejecta contains 0.6-0.8 M_☉ of 0.1 µm silicate grains, while the post-shock ejecta has 0.02-0.09 M_☉ of 5-10 nm grains in dense clumps, and 2 ×10^–3 M_☉ of 0.1 µm grains in the diffuse X-ray emitting shocked ejecta. The implied dust destruction efficiency is 74-94 percent in the clumps and 92-98 percent overall, giving Cas A a final dust yield of 0.05-0.30 M_☉. If the unshocked ejecta grains are larger than 0.1 µm, the dust masses are higher, the destruction efficiencies are lower, and the final yield may exceed 0.5 M_☉. As Cas A has a dense circumstellar environment and thus a much stronger reverse shock than is typical, the average dust destruction efficiency across all CCSNe is likely to be lower, and the average dust yield higher. This supports a mostly stellar origin for the cosmic dust budget.