Ion acceleration and stability in the radiation pressure dominated regime

We investigate the stability against the onset of Rayleigh-Taylor modes of a thin plasma foil accelerated by the radiation pressure. We are interested in the process of ion acceleration in the interaction between a plasma foil and an ultraintense laser pulse in the so-called Radiation Pressure Dominated Regime. We show that in the relativistic regime the Rayleigh-Taylor instability develops more slowly than in the non-relativistic regime. We show that the onset of the Rayleigh-Taylor-like instability leads to the formation of high-density, high-energy plasma clumps and to a relatively higher rate of ion acceleration in the regions between the clumps.