Ambient pressure and single-bubble sonoluminescence

We present a theoretical analysis of the influence of ambient pressure on single-bubble sonoluminescence (SBSL). By combining simulations of gas dynamics, mass diffusion theory, and stability analysis we find a narrow region of the parameter space where stable SBSL is possible. In particular, the theory predicts a 200% increase in SL radiation if ambient pressure is decreased only 5%. The results are compared with preliminary experimental data, and a good agreement is found. Variation of ambient pressure provides a simple and interesting test for the validity of various SL theories, diffusive or nondiffusive mass flow ideas, and stability analyses.