Efficient quasi-monoenergetic ion beams from laser-driven relativistic plasmas.

Table-top laser-plasma ion accelerators have many exciting applications, many of which require ion beams with simultaneous narrow energy spread and high conversion efficiency. However, achieving these requirements has been elusive. Here we report the experimental demonstration of laser-driven ion beams with narrow energy spread and energies up to 18 MeV per nucleon and ∼5% conversion efficiency (that is 4 J out of 80-J laser).

Ionization of methane in strong and ultrastrong relativistic fields.

The photoionization of methane is reported for intensities up to 10(19) W/cm2 with linear and circular polarized light. While fragmental ions (e.g.