Is Sonoluminescence due to Collision-Induced Emission?

We estimate the collision-induced emission (CIE) intensity and profile in the visible and near UV region of the spectrum of $N_2-X$ pairs where $X$ represents another ${\mathrm{N}}_2$ molecule or an argon atom, etc. of shock waves believed to exist in sonoluminescence experiments. Calculated profiles consist of superimposed high overtone bands and resemble the measured profiles. Intensities calculated on the basis of a few, simple assumptions concerning the induced dipole surface compare favorably with measurements. The agreement obtained suggests that CIE is an attractive alternative to bremsstrahlung to explain sonoluminescence. The CIE source is optically thin, and the spectral emission profile is not related to Planck's law.