Comparison of Xe single bubble sonoluminescence in water and sulfuric acid

Using the equations of fluid mechanics with proper boundaryconditions and taking account of the gas properties, we cannumerically simulate the process of single bubble sonoluminescence,in which electron--neutral atom bremsstrahlung, electron--ionbremsstrahlung and recombination radiation, and the radiativeattachment of electrons to atoms and molecules contribute to thelight emission. The calculation can quantitatively or qualitativelyinterpret the experimental results. We find that the accumulatedheat energy inside the compressed gas bubble is mostly consumed bythe chemical reaction, therefore, the maximum degree of ionizationinside Xe bubble in water is much lower than that in sulfuric acid,of which the vapour pressure is very low. In addition, in sulfuricacid much larger $p_{rm a}$ and $R_{0}$ are allowed which makes thebubbles in it much brighter than that in water.