Energetic ions from next generation ultraintense ultrashort lasers: Scaling laws for Target Normal Sheath Acceleration

Laser-driven ion acceleration represents one of the most exciting topics related to the physics of laser-plasma interaction. Ions can be effectively accelerated up to multi-MeV energies via the so-called Target Normal Sheath Acceleration (TNSA) mechanism. The possibility of predicting the properties of the accelerated ions is definitely a crucial issue, both from a fundamental point of view and in the light of foreseen applications. In this work the problem of the dependence of the maximum ion energy achieved in TNSA on the laser properties is theoretically investigated. Particular attention is devoted to elucidate the role played by the various laser parameters, like power, intensity, energy and focal spot, in determining the maximum ion energy, with special focus to values relevant for the present and next generation of Ti:Sa laser systems.