Fig. 1: The schematic diagram of interspecies radiative transition in superdense plasmas.
From: Interspecies radiative transition in warm and superdense plasma mixtures
Due to the high compression of superdense plasmas, ions of different species can get so close to each other that their atomic states may become overlapping. In such a superdense environment, photon-pumping or collision-induced 1s-core holes can be filled by 2p electrons from other species, giving rise to inter-atomic Kα emission.
