Mysteries and Unknows of Single Bubble Sonoluminescence from Viewpoint of Plasma Spectroscopy

Abstract

UV continua observed in multi-bubble and single-bubble sonoluminescence spectra of hydrogen-containing liquids have the same physical nature - radiative dissociation of electronically excited hydrogen molecules (and possibly hydrides of heavy rare gases like ArH). In the case of SBSL of "air bubble in water" the oscillating bubble actually consists of a hydrogen/argon mixture with periodically changing amount of water vapor. The proposed mechanism is able to explain all available spectroscopic observations without any exotic hypothesis but in terms usual for plasma spectroscopy.