THE ANGULAR-DISTRIBUTION OF ATOMIC IONS FOLLOWING THE MULTIPHOTON IONIZATION OF CARBON-MONOXIDE

A laser of wavelength 600 nm, pulse length 0.6 ps and focused intensity approximately=3*1015 W cm2 is used to multiply ionise CO molecules. The fragmentation channels, for example (CO3+) implies C2++O+, are isolated using a form of triple coincidence called covariance mapping. The angular distribution of the various atomic ion pairs is found to be strongly peaked along the E vector of the highly linearly polarised laser and to a degree that increases slowly with ionisation stage.