Blowout regimes of plasma wakefield acceleration

A wide region of beam parameters is numerically scanned and the dependence of wakefield properties on the beam length and current is clarified for the blowout regime of beam-plasma interaction. The main regimes of the plasma response are found, which qualitatively differ in the plasma behavior. To characterize the efficiency of the energy exchange between the beam and the plasma, the energy flux through the comoving window is introduced. Scalings of the energy flux for the linear plasma response and the main blowout regimes are studied. The most efficient energy transfer occurs in the so-called "strong beam" regime of interaction. For this regime, analytical approximations for various aspects of the plasma response are obtained.