MeV negative ion generation from ultra-intense laser interaction with a water spray

摘要

MeV negative oxygen ions are obtained from a water spray target irradiated by high intensity (5×10~(19) W/cm~2) and ultrashort (50 fs) laser pulses. Generation of negative ions is ascribed to electron-capture processes that the laser-accelerated high-energy positive ion experiences when it interacts with atoms in the spray. This mechanism implies the existence of a large number of MeV neutral oxygen atoms, which is consistent with indirect experimental evidence.