Nature of third continua in rare gases

摘要

The studies on third continua in rare gases carried out over the last decade are considered. The comprehensive analysis of the available experimental data confirms our earlier interpretation of the nature of third continua. When dense rare gases (at a pressure on the order of and higher than one atmosphere) are excited with a hard ionizer (electron or ion beams or short-wavelength photons), the dominant contribution to the emission of third continua comes from transitions of singly charged dimer ions from the first electronically excited bound states to repulsive states correlated with the ground electronic states of ions and atoms.