The Turbulent Destruction of Clouds - II. Mach Number Dependence,
  Mass-loss Rates, and Tail Formation
  The turbulent destruction of a cloud subject to the passage of an adiabatic
shock is studied. We find large discrepancies between the lifetime of the cloud
and the analytical result of Hartquist et al. (1986). These differences appear
to be due to the assumption in Hartquist et al. that mass-loss occurs largely
as a result of lower pressure regions on the surface of the cloud away from the
stagnation point, whereas in reality Kelvin-Helmholtz (KH) instabilities play a
dominant role in the cloud destruction. We find that the true lifetime of the
cloud (defined as when all of the material from the core of the cloud is well
mixed with the intercloud material in the hydrodynamic cells) is about 6 times
t_KHD, where t_KHD is the growth timescale for the most disruptive,
long-wavelength, KH instabilities. These findings have wide implications for
diffuse sources where there is transfer of material between hot and cool
phases.
  The properties of the interaction as a function of Mach number and cloud
density contrast are also studied. The interaction is milder at lower Mach
numbers with the most marked differences occuring at low shock Mach numbers
when the postshock gas is subsonic with respect to the cloud (i.e. M < 2.76).
Material stripped off the cloud only forms a long "tail-like" feature if the
density contrast of the cloud to the ambient medium, chi > 1e3.
