Angle-resolved covariance mapping of spatially-aligned CO₂²⁺ in an intense picosecond laser field

Abstract

Angle-resolved covariance mapping has been applied to measure the angular distributions of C⁺ -O⁺ and CO⁺-O⁺ ion pairs resulting from double ionization of CO₂ using picosecond-duration, linearly-polarized laser pulses of intensity ~10^L3 W cm^-2, CO₂²⁺ is spatially aligned along the laser polarization vector much more efficiently than CO₂⁺. The field-induced dipole moment of the dication is calculated to be 21% more than that of the cation. The following sequence of events is inferred upon immersion of CO₂ in the intense field: ionization and double ionization ^→ spatial alignment ^→ dissociation.