V1663 Aquilae: A Fast Fe ii-type Nova that Formed Dust and Coronal Lines

Abstract V1663 Aquilae was a rare nova that formed both dust and coronal emission lines. A spectrum from 157 days after peak brightness shows both thermal dust emission and coronal emission present at the same epoch. An earlier spectrum from 36 days post maximum captures the nova prior to the formation of either dust or high-excitation emission lines. At the earlier epoch, its emission lines arose mostly from neutral species and singly ionized iron.