Intense Field Ionization of Methane, Ethane, Butane, and Octane: Transition from Molecular to Atomic Response

摘要

Ion yields of C{sup}(+n) (n<6) from methane, ethane, butane and octane are measured from 10{sup}13 W/cm{sup}2 to 10{sup}19 W/cm{sup}2, with photoelectron spectra up to 0.5 MeV. As one reaches 10{sup}17 W/cm{sup}2 the molecular response becomes atomic-like.