The hydrodynamics of plasma ablation and the thermalization
process of the target interior core with the surrounding
corona, formed by the uniform irradiation of intense ion
beams over the spherical target are investigated in detail.
Starting from the basic equations for the ion beam, the
ion beam penetration depth is calculated and the self-regulation
condition for the hot corona is applied to describe the
process of core-corona coupling. The effects of ion beam
energy, ion beam mass, and the target electron density
on the ion beam penetration depth are studied. As the relevant
calculations reveal, it is interesting to note the existence
of an optimum value of ion beam energy for which the core-corona
coupling attains maximum value, beyond which further increase
of the ion beam energy leads to the formation of more tenuous
corona only and the target interior core begins to decouple
from the surrounding corona.