\begin{abstract}
We studied the dependence of thermodynamic variables in a sonoluminescing
bubble on various physical factors, which include viscosity, thermal
conductivity, surface tension, the equation of state of the gas inside the
bubble, as well as the compressibility of the surrounding liquid.  The
numerical solutions show that the existence of shock waves in the SL parameter
regime is very sensitive to these factors.  Furthermore, we show that even
without shock waves, the reflection of continuous compressional waves at the
bubble center can produce the high temperature and picosecond time scale light
pulse of the SL bubble, which implies that SL may not necessarily be due to
shock waves.

\end{abstract}
\pacs{PACS numbers: 78.60.Mq, 47.40.-x, 44.10.+i, 43.25.+y}