Modeling a sonoluminescing bubble as a plasma

We present detailed simulations of the optical spectra emitted from an Argo n plasma whose conditions correspond to those thought to prevail within son oluminescing bubbles. The model incorporates detailed atomic physics based on atomic data from the Opacity Project database, and includes bound-bound, bound-free, and free-free transitions. Line broadening is treated by use o f the modified semi-empirical method. The spectral model is used as a postp rocessor of hydrodynamic simulations. We find good agreement with experimen tal spectra and accurately reproduce experimental pulse widths. We also pre dict that whilst the majority of the optical emission corresponds to bound- free transitions, there remains the possibility of observing line emission in both the UV and IR regions of the spectrum. (C) 2001 Elsevier Science Lt d. All rights reserved.